scanline.cpp revision 3e292b9716072cae37bff5b99c1d2660555a265e
1/* libs/pixelflinger/scanline.cpp
2**
3** Copyright 2006, The Android Open Source Project
4**
5** Licensed under the Apache License, Version 2.0 (the "License");
6** you may not use this file except in compliance with the License.
7** You may obtain a copy of the License at
8**
9**     http://www.apache.org/licenses/LICENSE-2.0
10**
11** Unless required by applicable law or agreed to in writing, software
12** distributed under the License is distributed on an "AS IS" BASIS,
13** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14** See the License for the specific language governing permissions and
15** limitations under the License.
16*/
17
18
19#define LOG_TAG "pixelflinger"
20
21#include <assert.h>
22#include <stdlib.h>
23#include <stdio.h>
24#include <string.h>
25
26#include <cutils/memory.h>
27#include <cutils/log.h>
28
29#include "buffer.h"
30#include "scanline.h"
31
32#include "codeflinger/CodeCache.h"
33#include "codeflinger/GGLAssembler.h"
34#include "codeflinger/ARMAssembler.h"
35//#include "codeflinger/ARMAssemblerOptimizer.h"
36
37// ----------------------------------------------------------------------------
38
39#define ANDROID_CODEGEN_GENERIC     0   // force generic pixel pipeline
40#define ANDROID_CODEGEN_C           1   // hand-written C, fallback generic
41#define ANDROID_CODEGEN_ASM         2   // hand-written asm, fallback generic
42#define ANDROID_CODEGEN_GENERATED   3   // hand-written asm, fallback codegen
43
44#ifdef NDEBUG
45#   define ANDROID_RELEASE
46#   define ANDROID_CODEGEN      ANDROID_CODEGEN_GENERATED
47#else
48#   define ANDROID_DEBUG
49#   define ANDROID_CODEGEN      ANDROID_CODEGEN_GENERATED
50#endif
51
52#if defined(__arm__)
53#   define ANDROID_ARM_CODEGEN  1
54#else
55#   define ANDROID_ARM_CODEGEN  0
56#endif
57
58#define DEBUG__CODEGEN_ONLY     0
59
60
61#define ASSEMBLY_SCRATCH_SIZE   2048
62
63// ----------------------------------------------------------------------------
64namespace android {
65// ----------------------------------------------------------------------------
66
67static void init_y(context_t*, int32_t);
68static void init_y_noop(context_t*, int32_t);
69static void init_y_packed(context_t*, int32_t);
70static void init_y_error(context_t*, int32_t);
71
72static void step_y__generic(context_t* c);
73static void step_y__nop(context_t*);
74static void step_y__smooth(context_t* c);
75static void step_y__tmu(context_t* c);
76static void step_y__w(context_t* c);
77
78static void scanline(context_t* c);
79static void scanline_perspective(context_t* c);
80static void scanline_perspective_single(context_t* c);
81static void scanline_t32cb16blend(context_t* c);
82static void scanline_t32cb16(context_t* c);
83static void scanline_memcpy(context_t* c);
84static void scanline_memset8(context_t* c);
85static void scanline_memset16(context_t* c);
86static void scanline_memset32(context_t* c);
87static void scanline_noop(context_t* c);
88static void scanline_set(context_t* c);
89static void scanline_clear(context_t* c);
90
91static void rect_generic(context_t* c, size_t yc);
92static void rect_memcpy(context_t* c, size_t yc);
93
94extern "C" void scanline_t32cb16blend_arm(uint16_t*, uint32_t*, size_t);
95extern "C" void scanline_t32cb16_arm(uint16_t *dst, uint32_t *src, size_t ct);
96
97// ----------------------------------------------------------------------------
98
99struct shortcut_t {
100    needs_filter_t  filter;
101    const char*     desc;
102    void            (*scanline)(context_t*);
103    void            (*init_y)(context_t*, int32_t);
104};
105
106// Keep in sync with needs
107static shortcut_t shortcuts[] = {
108    { { { 0x03515104, 0x00000077, { 0x00000A01, 0x00000000 } },
109        { 0xFFFFFFFF, 0xFFFFFFFF, { 0xFFFFFFFF, 0x0000003F } } },
110        "565 fb, 8888 tx, blend", scanline_t32cb16blend, init_y_noop },
111    { { { 0x03010104, 0x00000077, { 0x00000A01, 0x00000000 } },
112        { 0xFFFFFFFF, 0xFFFFFFFF, { 0xFFFFFFFF, 0x0000003F } } },
113        "565 fb, 8888 tx", scanline_t32cb16, init_y_noop  },
114    { { { 0x00000000, 0x00000000, { 0x00000000, 0x00000000 } },
115        { 0x00000000, 0x00000007, { 0x00000000, 0x00000000 } } },
116        "(nop) alpha test", scanline_noop, init_y_noop },
117    { { { 0x00000000, 0x00000000, { 0x00000000, 0x00000000 } },
118        { 0x00000000, 0x00000070, { 0x00000000, 0x00000000 } } },
119        "(nop) depth test", scanline_noop, init_y_noop },
120    { { { 0x05000000, 0x00000000, { 0x00000000, 0x00000000 } },
121        { 0x0F000000, 0x00000080, { 0x00000000, 0x00000000 } } },
122        "(nop) logic_op", scanline_noop, init_y_noop },
123    { { { 0xF0000000, 0x00000000, { 0x00000000, 0x00000000 } },
124        { 0xF0000000, 0x00000080, { 0x00000000, 0x00000000 } } },
125        "(nop) color mask", scanline_noop, init_y_noop },
126    { { { 0x0F000000, 0x00000077, { 0x00000000, 0x00000000 } },
127        { 0xFF000000, 0x000000F7, { 0x00000000, 0x00000000 } } },
128        "(set) logic_op", scanline_set, init_y_noop },
129    { { { 0x00000000, 0x00000077, { 0x00000000, 0x00000000 } },
130        { 0xFF000000, 0x000000F7, { 0x00000000, 0x00000000 } } },
131        "(clear) logic_op", scanline_clear, init_y_noop },
132    { { { 0x03000000, 0x00000077, { 0x00000000, 0x00000000 } },
133        { 0xFFFFFF00, 0x000000F7, { 0x00000000, 0x00000000 } } },
134        "(clear) blending 0/0", scanline_clear, init_y_noop },
135    { { { 0x00000000, 0x00000000, { 0x00000000, 0x00000000 } },
136        { 0x0000003F, 0x00000000, { 0x00000000, 0x00000000 } } },
137        "(error) invalid color-buffer format", scanline_noop, init_y_error },
138};
139static const needs_filter_t noblend1to1 = {
140        // (disregard dithering, see below)
141        { 0x03010100, 0x00000077, { 0x00000A00, 0x00000000 } },
142        { 0xFFFFFFC0, 0xFFFFFEFF, { 0xFFFFFFC0, 0x0000003F } }
143};
144static  const needs_filter_t fill16noblend = {
145        { 0x03010100, 0x00000077, { 0x00000000, 0x00000000 } },
146        { 0xFFFFFFC0, 0xFFFFFFFF, { 0x0000003F, 0x0000003F } }
147};
148
149// ----------------------------------------------------------------------------
150
151#if ANDROID_ARM_CODEGEN
152static CodeCache gCodeCache(12 * 1024);
153
154class ScanlineAssembly : public Assembly {
155    AssemblyKey<needs_t> mKey;
156public:
157    ScanlineAssembly(needs_t needs, size_t size)
158        : Assembly(size), mKey(needs) { }
159    const AssemblyKey<needs_t>& key() const { return mKey; }
160};
161#endif
162
163// ----------------------------------------------------------------------------
164
165void ggl_init_scanline(context_t* c)
166{
167    c->init_y = init_y;
168    c->step_y = step_y__generic;
169    c->scanline = scanline;
170}
171
172void ggl_uninit_scanline(context_t* c)
173{
174    if (c->state.buffers.coverage)
175        free(c->state.buffers.coverage);
176#if ANDROID_ARM_CODEGEN
177    if (c->scanline_as)
178        c->scanline_as->decStrong(c);
179#endif
180}
181
182// ----------------------------------------------------------------------------
183
184static void pick_scanline(context_t* c)
185{
186#if (!defined(DEBUG__CODEGEN_ONLY) || (DEBUG__CODEGEN_ONLY == 0))
187
188#if ANDROID_CODEGEN == ANDROID_CODEGEN_GENERIC
189    c->init_y = init_y;
190    c->step_y = step_y__generic;
191    c->scanline = scanline;
192    return;
193#endif
194
195    //printf("*** needs [%08lx:%08lx:%08lx:%08lx]\n",
196    //    c->state.needs.n, c->state.needs.p,
197    //    c->state.needs.t[0], c->state.needs.t[1]);
198
199    // first handle the special case that we cannot test with a filter
200    const uint32_t cb_format = GGL_READ_NEEDS(CB_FORMAT, c->state.needs.n);
201    if (GGL_READ_NEEDS(T_FORMAT, c->state.needs.t[0]) == cb_format) {
202        if (c->state.needs.match(noblend1to1)) {
203            // this will match regardless of dithering state, since both
204            // src and dest have the same format anyway, there is no dithering
205            // to be done.
206            const GGLFormat* f =
207                &(c->formats[GGL_READ_NEEDS(T_FORMAT, c->state.needs.t[0])]);
208            if ((f->components == GGL_RGB) ||
209                (f->components == GGL_RGBA) ||
210                (f->components == GGL_LUMINANCE) ||
211                (f->components == GGL_LUMINANCE_ALPHA))
212            {
213                // format must have all of RGB components
214                // (so the current color doesn't show through)
215                c->scanline = scanline_memcpy;
216                c->init_y = init_y_noop;
217                return;
218            }
219        }
220    }
221
222    if (c->state.needs.match(fill16noblend)) {
223        c->init_y = init_y_packed;
224        switch (c->formats[cb_format].size) {
225        case 1: c->scanline = scanline_memset8;  return;
226        case 2: c->scanline = scanline_memset16; return;
227        case 4: c->scanline = scanline_memset32; return;
228        }
229    }
230
231    const int numFilters = sizeof(shortcuts)/sizeof(shortcut_t);
232    for (int i=0 ; i<numFilters ; i++) {
233        if (c->state.needs.match(shortcuts[i].filter)) {
234            c->scanline = shortcuts[i].scanline;
235            c->init_y = shortcuts[i].init_y;
236            return;
237        }
238    }
239
240#endif // DEBUG__CODEGEN_ONLY
241
242    c->init_y = init_y;
243    c->step_y = step_y__generic;
244
245#if ANDROID_ARM_CODEGEN
246    // we're going to have to generate some code...
247    // here, generate code for our pixel pipeline
248    const AssemblyKey<needs_t> key(c->state.needs);
249    sp<Assembly> assembly = gCodeCache.lookup(key);
250    if (assembly == 0) {
251        // create a new assembly region
252        sp<ScanlineAssembly> a = new ScanlineAssembly(c->state.needs,
253                ASSEMBLY_SCRATCH_SIZE);
254        // initialize our assembler
255        GGLAssembler assembler( new ARMAssembler(a) );
256        //GGLAssembler assembler(
257        //        new ARMAssemblerOptimizer(new ARMAssembler(a)) );
258        // generate the scanline code for the given needs
259        int err = assembler.scanline(c->state.needs, c);
260        if (ggl_likely(!err)) {
261            // finally, cache this assembly
262            err = gCodeCache.cache(a->key(), a);
263        }
264        if (ggl_unlikely(err)) {
265            LOGE("error generating or caching assembly. Reverting to NOP.");
266            c->scanline = scanline_noop;
267            c->init_y = init_y_noop;
268            c->step_y = step_y__nop;
269            return;
270        }
271        assembly = a;
272    }
273
274    // release the previous assembly
275    if (c->scanline_as) {
276        c->scanline_as->decStrong(c);
277    }
278
279    //LOGI("using generated pixel-pipeline");
280    c->scanline_as = assembly.get();
281    c->scanline_as->incStrong(c); //  hold on to assembly
282    c->scanline = (void(*)(context_t* c))assembly->base();
283#else
284//    LOGW("using generic (slow) pixel-pipeline");
285    c->scanline = scanline;
286#endif
287}
288
289void ggl_pick_scanline(context_t* c)
290{
291    pick_scanline(c);
292    if ((c->state.enables & GGL_ENABLE_W) &&
293        (c->state.enables & GGL_ENABLE_TMUS))
294    {
295        c->span = c->scanline;
296        c->scanline = scanline_perspective;
297        if (!(c->state.enabled_tmu & (c->state.enabled_tmu - 1))) {
298            // only one TMU enabled
299            c->scanline = scanline_perspective_single;
300        }
301    }
302}
303
304// ----------------------------------------------------------------------------
305
306static void blending(context_t* c, pixel_t* fragment, pixel_t* fb);
307static void blend_factor(context_t* c, pixel_t* r, uint32_t factor,
308        const pixel_t* src, const pixel_t* dst);
309static void rescale(uint32_t& u, uint8_t& su, uint32_t& v, uint8_t& sv);
310
311#if ANDROID_ARM_CODEGEN && (ANDROID_CODEGEN == ANDROID_CODEGEN_GENERATED)
312
313// no need to compile the generic-pipeline, it can't be reached
314void scanline(context_t*)
315{
316}
317
318#else
319
320void rescale(uint32_t& u, uint8_t& su, uint32_t& v, uint8_t& sv)
321{
322    if (su && sv) {
323        if (su > sv) {
324            v = ggl_expand(v, sv, su);
325            sv = su;
326        } else if (su < sv) {
327            u = ggl_expand(u, su, sv);
328            su = sv;
329        }
330    }
331}
332
333void blending(context_t* c, pixel_t* fragment, pixel_t* fb)
334{
335    rescale(fragment->c[0], fragment->s[0], fb->c[0], fb->s[0]);
336    rescale(fragment->c[1], fragment->s[1], fb->c[1], fb->s[1]);
337    rescale(fragment->c[2], fragment->s[2], fb->c[2], fb->s[2]);
338    rescale(fragment->c[3], fragment->s[3], fb->c[3], fb->s[3]);
339
340    pixel_t sf, df;
341    blend_factor(c, &sf, c->state.blend.src, fragment, fb);
342    blend_factor(c, &df, c->state.blend.dst, fragment, fb);
343
344    fragment->c[1] =
345            gglMulAddx(fragment->c[1], sf.c[1], gglMulx(fb->c[1], df.c[1]));
346    fragment->c[2] =
347            gglMulAddx(fragment->c[2], sf.c[2], gglMulx(fb->c[2], df.c[2]));
348    fragment->c[3] =
349            gglMulAddx(fragment->c[3], sf.c[3], gglMulx(fb->c[3], df.c[3]));
350
351    if (c->state.blend.alpha_separate) {
352        blend_factor(c, &sf, c->state.blend.src_alpha, fragment, fb);
353        blend_factor(c, &df, c->state.blend.dst_alpha, fragment, fb);
354    }
355
356    fragment->c[0] =
357            gglMulAddx(fragment->c[0], sf.c[0], gglMulx(fb->c[0], df.c[0]));
358
359    // clamp to 1.0
360    if (fragment->c[0] >= (1LU<<fragment->s[0]))
361        fragment->c[0] = (1<<fragment->s[0])-1;
362    if (fragment->c[1] >= (1LU<<fragment->s[1]))
363        fragment->c[1] = (1<<fragment->s[1])-1;
364    if (fragment->c[2] >= (1LU<<fragment->s[2]))
365        fragment->c[2] = (1<<fragment->s[2])-1;
366    if (fragment->c[3] >= (1LU<<fragment->s[3]))
367        fragment->c[3] = (1<<fragment->s[3])-1;
368}
369
370static inline int blendfactor(uint32_t x, uint32_t size, uint32_t def = 0)
371{
372    if (!size)
373        return def;
374
375    // scale to 16 bits
376    if (size > 16) {
377        x >>= (size - 16);
378    } else if (size < 16) {
379        x = ggl_expand(x, size, 16);
380    }
381    x += x >> 15;
382    return x;
383}
384
385void blend_factor(context_t* c, pixel_t* r,
386        uint32_t factor, const pixel_t* src, const pixel_t* dst)
387{
388    switch (factor) {
389        case GGL_ZERO:
390            r->c[1] =
391            r->c[2] =
392            r->c[3] =
393            r->c[0] = 0;
394            break;
395        case GGL_ONE:
396            r->c[1] =
397            r->c[2] =
398            r->c[3] =
399            r->c[0] = FIXED_ONE;
400            break;
401        case GGL_DST_COLOR:
402            r->c[1] = blendfactor(dst->c[1], dst->s[1]);
403            r->c[2] = blendfactor(dst->c[2], dst->s[2]);
404            r->c[3] = blendfactor(dst->c[3], dst->s[3]);
405            r->c[0] = blendfactor(dst->c[0], dst->s[0]);
406            break;
407        case GGL_SRC_COLOR:
408            r->c[1] = blendfactor(src->c[1], src->s[1]);
409            r->c[2] = blendfactor(src->c[2], src->s[2]);
410            r->c[3] = blendfactor(src->c[3], src->s[3]);
411            r->c[0] = blendfactor(src->c[0], src->s[0]);
412            break;
413        case GGL_ONE_MINUS_DST_COLOR:
414            r->c[1] = FIXED_ONE - blendfactor(dst->c[1], dst->s[1]);
415            r->c[2] = FIXED_ONE - blendfactor(dst->c[2], dst->s[2]);
416            r->c[3] = FIXED_ONE - blendfactor(dst->c[3], dst->s[3]);
417            r->c[0] = FIXED_ONE - blendfactor(dst->c[0], dst->s[0]);
418            break;
419        case GGL_ONE_MINUS_SRC_COLOR:
420            r->c[1] = FIXED_ONE - blendfactor(src->c[1], src->s[1]);
421            r->c[2] = FIXED_ONE - blendfactor(src->c[2], src->s[2]);
422            r->c[3] = FIXED_ONE - blendfactor(src->c[3], src->s[3]);
423            r->c[0] = FIXED_ONE - blendfactor(src->c[0], src->s[0]);
424            break;
425        case GGL_SRC_ALPHA:
426            r->c[1] =
427            r->c[2] =
428            r->c[3] =
429            r->c[0] = blendfactor(src->c[0], src->s[0], FIXED_ONE);
430            break;
431        case GGL_ONE_MINUS_SRC_ALPHA:
432            r->c[1] =
433            r->c[2] =
434            r->c[3] =
435            r->c[0] = FIXED_ONE - blendfactor(src->c[0], src->s[0], FIXED_ONE);
436            break;
437        case GGL_DST_ALPHA:
438            r->c[1] =
439            r->c[2] =
440            r->c[3] =
441            r->c[0] = blendfactor(dst->c[0], dst->s[0], FIXED_ONE);
442            break;
443        case GGL_ONE_MINUS_DST_ALPHA:
444            r->c[1] =
445            r->c[2] =
446            r->c[3] =
447            r->c[0] = FIXED_ONE - blendfactor(dst->c[0], dst->s[0], FIXED_ONE);
448            break;
449        case GGL_SRC_ALPHA_SATURATE:
450            // XXX: GGL_SRC_ALPHA_SATURATE
451            break;
452    }
453}
454
455static GGLfixed wrapping(int32_t coord, uint32_t size, int tx_wrap)
456{
457    GGLfixed d;
458    if (tx_wrap == GGL_REPEAT) {
459        d = (uint32_t(coord)>>16) * size;
460    } else if (tx_wrap == GGL_CLAMP) { // CLAMP_TO_EDGE semantics
461        const GGLfixed clamp_min = FIXED_HALF;
462        const GGLfixed clamp_max = (size << 16) - FIXED_HALF;
463        if (coord < clamp_min)     coord = clamp_min;
464        if (coord > clamp_max)     coord = clamp_max;
465        d = coord;
466    } else { // 1:1
467        const GGLfixed clamp_min = 0;
468        const GGLfixed clamp_max = (size << 16);
469        if (coord < clamp_min)     coord = clamp_min;
470        if (coord > clamp_max)     coord = clamp_max;
471        d = coord;
472    }
473    return d;
474}
475
476static inline
477GGLcolor ADJUST_COLOR_ITERATOR(GGLcolor v, GGLcolor dvdx, int len)
478{
479    const int32_t end = dvdx * (len-1) + v;
480    if (end < 0)
481        v -= end;
482    v &= ~(v>>31);
483    return v;
484}
485
486void scanline(context_t* c)
487{
488    const uint32_t enables = c->state.enables;
489    const int xs = c->iterators.xl;
490    const int x1 = c->iterators.xr;
491	int xc = x1 - xs;
492    const int16_t* covPtr = c->state.buffers.coverage + xs;
493
494    // All iterated values are sampled at the pixel center
495
496    // reset iterators for that scanline...
497    GGLcolor r, g, b, a;
498    iterators_t& ci = c->iterators;
499    if (enables & GGL_ENABLE_SMOOTH) {
500        r = (xs * c->shade.drdx) + ci.ydrdy;
501        g = (xs * c->shade.dgdx) + ci.ydgdy;
502        b = (xs * c->shade.dbdx) + ci.ydbdy;
503        a = (xs * c->shade.dadx) + ci.ydady;
504        r = ADJUST_COLOR_ITERATOR(r, c->shade.drdx, xc);
505        g = ADJUST_COLOR_ITERATOR(g, c->shade.dgdx, xc);
506        b = ADJUST_COLOR_ITERATOR(b, c->shade.dbdx, xc);
507        a = ADJUST_COLOR_ITERATOR(a, c->shade.dadx, xc);
508    } else {
509        r = ci.ydrdy;
510        g = ci.ydgdy;
511        b = ci.ydbdy;
512        a = ci.ydady;
513    }
514
515    // z iterators are 1.31
516    GGLfixed z = (xs * c->shade.dzdx) + ci.ydzdy;
517    GGLfixed f = (xs * c->shade.dfdx) + ci.ydfdy;
518
519    struct {
520        GGLfixed s, t;
521    } tc[GGL_TEXTURE_UNIT_COUNT];
522    if (enables & GGL_ENABLE_TMUS) {
523        for (int i=0 ; i<GGL_TEXTURE_UNIT_COUNT ; ++i) {
524            if (c->state.texture[i].enable) {
525                texture_iterators_t& ti = c->state.texture[i].iterators;
526                if (enables & GGL_ENABLE_W) {
527                    tc[i].s = ti.ydsdy;
528                    tc[i].t = ti.ydtdy;
529                } else {
530                    tc[i].s = (xs * ti.dsdx) + ti.ydsdy;
531                    tc[i].t = (xs * ti.dtdx) + ti.ydtdy;
532                }
533            }
534        }
535    }
536
537    pixel_t fragment;
538    pixel_t texel;
539    pixel_t fb;
540
541	uint32_t x = xs;
542	uint32_t y = c->iterators.y;
543
544	while (xc--) {
545
546        { // just a scope
547
548		// read color (convert to 8 bits by keeping only the integer part)
549        fragment.s[1] = fragment.s[2] =
550        fragment.s[3] = fragment.s[0] = 8;
551        fragment.c[1] = r >> (GGL_COLOR_BITS-8);
552        fragment.c[2] = g >> (GGL_COLOR_BITS-8);
553        fragment.c[3] = b >> (GGL_COLOR_BITS-8);
554        fragment.c[0] = a >> (GGL_COLOR_BITS-8);
555
556		// texturing
557        if (enables & GGL_ENABLE_TMUS) {
558            for (int i=0 ; i<GGL_TEXTURE_UNIT_COUNT ; ++i) {
559                texture_t& tx = c->state.texture[i];
560                if (!tx.enable)
561                    continue;
562                texture_iterators_t& ti = tx.iterators;
563                int32_t u, v;
564
565                // s-coordinate
566                if (tx.s_coord != GGL_ONE_TO_ONE) {
567                    const int w = tx.surface.width;
568                    u = wrapping(tc[i].s, w, tx.s_wrap);
569                    tc[i].s += ti.dsdx;
570                } else {
571                    u = (((tx.shade.is0>>16) + x)<<16) + FIXED_HALF;
572                }
573
574                // t-coordinate
575                if (tx.t_coord != GGL_ONE_TO_ONE) {
576                    const int h = tx.surface.height;
577                    v = wrapping(tc[i].t, h, tx.t_wrap);
578                    tc[i].t += ti.dtdx;
579                } else {
580                    v = (((tx.shade.it0>>16) + y)<<16) + FIXED_HALF;
581                }
582
583                // read texture
584                if (tx.mag_filter == GGL_NEAREST &&
585                    tx.min_filter == GGL_NEAREST)
586                {
587                    u >>= 16;
588                    v >>= 16;
589                    tx.surface.read(&tx.surface, c, u, v, &texel);
590                } else {
591                    const int w = tx.surface.width;
592                    const int h = tx.surface.height;
593                    u -= FIXED_HALF;
594                    v -= FIXED_HALF;
595                    int u0 = u >> 16;
596                    int v0 = v >> 16;
597                    int u1 = u0 + 1;
598                    int v1 = v0 + 1;
599                    if (tx.s_wrap == GGL_REPEAT) {
600                        if (u0<0)  u0 += w;
601                        if (u1<0)  u1 += w;
602                        if (u0>=w) u0 -= w;
603                        if (u1>=w) u1 -= w;
604                    } else {
605                        if (u0<0)  u0 = 0;
606                        if (u1<0)  u1 = 0;
607                        if (u0>=w) u0 = w-1;
608                        if (u1>=w) u1 = w-1;
609                    }
610                    if (tx.t_wrap == GGL_REPEAT) {
611                        if (v0<0)  v0 += h;
612                        if (v1<0)  v1 += h;
613                        if (v0>=h) v0 -= h;
614                        if (v1>=h) v1 -= h;
615                    } else {
616                        if (v0<0)  v0 = 0;
617                        if (v1<0)  v1 = 0;
618                        if (v0>=h) v0 = h-1;
619                        if (v1>=h) v1 = h-1;
620                    }
621                    pixel_t texels[4];
622                    uint32_t mm[4];
623                    tx.surface.read(&tx.surface, c, u0, v0, &texels[0]);
624                    tx.surface.read(&tx.surface, c, u0, v1, &texels[1]);
625                    tx.surface.read(&tx.surface, c, u1, v0, &texels[2]);
626                    tx.surface.read(&tx.surface, c, u1, v1, &texels[3]);
627                    u = (u >> 12) & 0xF;
628                    v = (v >> 12) & 0xF;
629                    u += u>>3;
630                    v += v>>3;
631                    mm[0] = (0x10 - u) * (0x10 - v);
632                    mm[1] = (0x10 - u) * v;
633                    mm[2] = u * (0x10 - v);
634                    mm[3] = 0x100 - (mm[0] + mm[1] + mm[2]);
635                    for (int j=0 ; j<4 ; j++) {
636                        texel.s[j] = texels[0].s[j];
637                        if (!texel.s[j]) continue;
638                        texel.s[j] += 8;
639                        texel.c[j] =    texels[0].c[j]*mm[0] +
640                                        texels[1].c[j]*mm[1] +
641                                        texels[2].c[j]*mm[2] +
642                                        texels[3].c[j]*mm[3] ;
643                    }
644                }
645
646                // Texture environnement...
647                for (int j=0 ; j<4 ; j++) {
648                    uint32_t& Cf = fragment.c[j];
649                    uint32_t& Ct = texel.c[j];
650                    uint8_t& sf  = fragment.s[j];
651                    uint8_t& st  = texel.s[j];
652                    uint32_t At = texel.c[0];
653                    uint8_t sat = texel.s[0];
654                    switch (tx.env) {
655                    case GGL_REPLACE:
656                        if (st) {
657                            Cf = Ct;
658                            sf = st;
659                        }
660                        break;
661                    case GGL_MODULATE:
662                        if (st) {
663                            uint32_t factor = Ct + (Ct>>(st-1));
664                            Cf = (Cf * factor) >> st;
665                        }
666                        break;
667                    case GGL_DECAL:
668                        if (sat) {
669                            rescale(Cf, sf, Ct, st);
670                            Cf += ((Ct - Cf) * (At + (At>>(sat-1)))) >> sat;
671                        }
672                        break;
673                    case GGL_BLEND:
674                        if (st) {
675                            uint32_t Cc = tx.env_color[i];
676                            if (sf>8)       Cc = (Cc * ((1<<sf)-1))>>8;
677                            else if (sf<8)  Cc = (Cc - (Cc>>(8-sf)))>>(8-sf);
678                            uint32_t factor = Ct + (Ct>>(st-1));
679                            Cf = ((((1<<st) - factor) * Cf) + Ct*Cc)>>st;
680                        }
681                        break;
682                    case GGL_ADD:
683                        if (st) {
684                            rescale(Cf, sf, Ct, st);
685                            Cf += Ct;
686                        }
687                        break;
688                    }
689                }
690            }
691		}
692
693        // coverage application
694        if (enables & GGL_ENABLE_AA) {
695            int16_t cf = *covPtr++;
696            fragment.c[0] = (int64_t(fragment.c[0]) * cf) >> 15;
697        }
698
699        // alpha-test
700        if (enables & GGL_ENABLE_ALPHA_TEST) {
701            GGLcolor ref = c->state.alpha_test.ref;
702            GGLcolor alpha = (uint64_t(fragment.c[0]) *
703                    ((1<<GGL_COLOR_BITS)-1)) / ((1<<fragment.s[0])-1);
704            switch (c->state.alpha_test.func) {
705            case GGL_NEVER:     goto discard;
706            case GGL_LESS:      if (alpha<ref)  break; goto discard;
707            case GGL_EQUAL:     if (alpha==ref) break; goto discard;
708            case GGL_LEQUAL:    if (alpha<=ref) break; goto discard;
709            case GGL_GREATER:   if (alpha>ref)  break; goto discard;
710            case GGL_NOTEQUAL:  if (alpha!=ref) break; goto discard;
711            case GGL_GEQUAL:    if (alpha>=ref) break; goto discard;
712            }
713        }
714
715        // depth test
716        if (c->state.buffers.depth.format) {
717            if (enables & GGL_ENABLE_DEPTH_TEST) {
718                surface_t* cb = &(c->state.buffers.depth);
719                uint16_t* p = (uint16_t*)(cb->data)+(x+(cb->stride*y));
720                uint16_t zz = uint32_t(z)>>(16);
721                uint16_t depth = *p;
722                switch (c->state.depth_test.func) {
723                case GGL_NEVER:     goto discard;
724                case GGL_LESS:      if (zz<depth)    break; goto discard;
725                case GGL_EQUAL:     if (zz==depth)   break; goto discard;
726                case GGL_LEQUAL:    if (zz<=depth)   break; goto discard;
727                case GGL_GREATER:   if (zz>depth)    break; goto discard;
728                case GGL_NOTEQUAL:  if (zz!=depth)   break; goto discard;
729                case GGL_GEQUAL:    if (zz>=depth)   break; goto discard;
730                }
731                // depth buffer is not enabled, if depth-test is not enabled
732/*
733        fragment.s[1] = fragment.s[2] =
734        fragment.s[3] = fragment.s[0] = 8;
735        fragment.c[1] =
736        fragment.c[2] =
737        fragment.c[3] =
738        fragment.c[0] = 255 - (zz>>8);
739*/
740                if (c->state.mask.depth) {
741                    *p = zz;
742                }
743            }
744        }
745
746        // fog
747        if (enables & GGL_ENABLE_FOG) {
748            for (int i=1 ; i<=3 ; i++) {
749                GGLfixed fc = (c->state.fog.color[i] * 0x10000) / 0xFF;
750                uint32_t& c = fragment.c[i];
751                uint8_t& s  = fragment.s[i];
752                c = (c * 0x10000) / ((1<<s)-1);
753                c = gglMulAddx(c, f, gglMulx(fc, 0x10000 - f));
754                s = 16;
755            }
756        }
757
758        // blending
759        if (enables & GGL_ENABLE_BLENDING) {
760            fb.c[1] = fb.c[2] = fb.c[3] = fb.c[0] = 0; // placate valgrind
761            fb.s[1] = fb.s[2] = fb.s[3] = fb.s[0] = 0;
762            c->state.buffers.color.read(
763                    &(c->state.buffers.color), c, x, y, &fb);
764            blending( c, &fragment, &fb );
765        }
766
767		// write
768        c->state.buffers.color.write(
769                &(c->state.buffers.color), c, x, y, &fragment);
770        }
771
772discard:
773		// iterate...
774        x += 1;
775        if (enables & GGL_ENABLE_SMOOTH) {
776            r += c->shade.drdx;
777            g += c->shade.dgdx;
778            b += c->shade.dbdx;
779            a += c->shade.dadx;
780        }
781        z += c->shade.dzdx;
782        f += c->shade.dfdx;
783	}
784}
785
786#endif // ANDROID_ARM_CODEGEN && (ANDROID_CODEGEN == ANDROID_CODEGEN_GENERATED)
787
788// ----------------------------------------------------------------------------
789#if 0
790#pragma mark -
791#pragma mark Scanline
792#endif
793
794template <typename T, typename U>
795static inline __attribute__((const))
796T interpolate(int y, T v0, U dvdx, U dvdy) {
797    // interpolates in pixel's centers
798    // v = v0 + (y + 0.5) * dvdy + (0.5 * dvdx)
799    return (y * dvdy) + (v0 + ((dvdy + dvdx) >> 1));
800}
801
802// ----------------------------------------------------------------------------
803#if 0
804#pragma mark -
805#endif
806
807void init_y(context_t* c, int32_t ys)
808{
809    const uint32_t enables = c->state.enables;
810
811    // compute iterators...
812    iterators_t& ci = c->iterators;
813
814    // sample in the center
815    ci.y = ys;
816
817    if (enables & (GGL_ENABLE_DEPTH_TEST|GGL_ENABLE_W|GGL_ENABLE_FOG)) {
818        ci.ydzdy = interpolate(ys, c->shade.z0, c->shade.dzdx, c->shade.dzdy);
819        ci.ydwdy = interpolate(ys, c->shade.w0, c->shade.dwdx, c->shade.dwdy);
820        ci.ydfdy = interpolate(ys, c->shade.f0, c->shade.dfdx, c->shade.dfdy);
821    }
822
823    if (ggl_unlikely(enables & GGL_ENABLE_SMOOTH)) {
824        ci.ydrdy = interpolate(ys, c->shade.r0, c->shade.drdx, c->shade.drdy);
825        ci.ydgdy = interpolate(ys, c->shade.g0, c->shade.dgdx, c->shade.dgdy);
826        ci.ydbdy = interpolate(ys, c->shade.b0, c->shade.dbdx, c->shade.dbdy);
827        ci.ydady = interpolate(ys, c->shade.a0, c->shade.dadx, c->shade.dady);
828        c->step_y = step_y__smooth;
829    } else {
830        ci.ydrdy = c->shade.r0;
831        ci.ydgdy = c->shade.g0;
832        ci.ydbdy = c->shade.b0;
833        ci.ydady = c->shade.a0;
834        // XXX: do only if needed, or make sure this is fast
835        c->packed = ggl_pack_color(c, c->state.buffers.color.format,
836                ci.ydrdy, ci.ydgdy, ci.ydbdy, ci.ydady);
837        c->packed8888 = ggl_pack_color(c, GGL_PIXEL_FORMAT_RGBA_8888,
838                ci.ydrdy, ci.ydgdy, ci.ydbdy, ci.ydady);
839    }
840
841    // initialize the variables we need in the shader
842    generated_vars_t& gen = c->generated_vars;
843    gen.argb[GGLFormat::ALPHA].c  = ci.ydady;
844    gen.argb[GGLFormat::ALPHA].dx = c->shade.dadx;
845    gen.argb[GGLFormat::RED  ].c  = ci.ydrdy;
846    gen.argb[GGLFormat::RED  ].dx = c->shade.drdx;
847    gen.argb[GGLFormat::GREEN].c  = ci.ydgdy;
848    gen.argb[GGLFormat::GREEN].dx = c->shade.dgdx;
849    gen.argb[GGLFormat::BLUE ].c  = ci.ydbdy;
850    gen.argb[GGLFormat::BLUE ].dx = c->shade.dbdx;
851    gen.dzdx = c->shade.dzdx;
852    gen.f    = ci.ydfdy;
853    gen.dfdx = c->shade.dfdx;
854
855    if (enables & GGL_ENABLE_TMUS) {
856        for (int i=0 ; i<GGL_TEXTURE_UNIT_COUNT ; ++i) {
857            texture_t& t = c->state.texture[i];
858            if (!t.enable) continue;
859
860            texture_iterators_t& ti = t.iterators;
861            if (t.s_coord == GGL_ONE_TO_ONE && t.t_coord == GGL_ONE_TO_ONE) {
862                // we need to set all of these to 0 because in some cases
863                // step_y__generic() or step_y__tmu() will be used and
864                // therefore will update dtdy, however, in 1:1 mode
865                // this is always done by the scanline rasterizer.
866                ti.dsdx = ti.dsdy = ti.dtdx = ti.dtdy = 0;
867                ti.ydsdy = t.shade.is0;
868                ti.ydtdy = t.shade.it0;
869            } else {
870                const int adjustSWrap = ((t.s_wrap==GGL_CLAMP)?0:16);
871                const int adjustTWrap = ((t.t_wrap==GGL_CLAMP)?0:16);
872                ti.sscale = t.shade.sscale + adjustSWrap;
873                ti.tscale = t.shade.tscale + adjustTWrap;
874                if (!(enables & GGL_ENABLE_W)) {
875                    // S coordinate
876                    const int32_t sscale = ti.sscale;
877                    const int32_t sy = interpolate(ys,
878                            t.shade.is0, t.shade.idsdx, t.shade.idsdy);
879                    if (sscale>=0) {
880                        ti.ydsdy= sy            << sscale;
881                        ti.dsdx = t.shade.idsdx << sscale;
882                        ti.dsdy = t.shade.idsdy << sscale;
883                    } else {
884                        ti.ydsdy= sy            >> -sscale;
885                        ti.dsdx = t.shade.idsdx >> -sscale;
886                        ti.dsdy = t.shade.idsdy >> -sscale;
887                    }
888                    // T coordinate
889                    const int32_t tscale = ti.tscale;
890                    const int32_t ty = interpolate(ys,
891                            t.shade.it0, t.shade.idtdx, t.shade.idtdy);
892                    if (tscale>=0) {
893                        ti.ydtdy= ty            << tscale;
894                        ti.dtdx = t.shade.idtdx << tscale;
895                        ti.dtdy = t.shade.idtdy << tscale;
896                    } else {
897                        ti.ydtdy= ty            >> -tscale;
898                        ti.dtdx = t.shade.idtdx >> -tscale;
899                        ti.dtdy = t.shade.idtdy >> -tscale;
900                    }
901                }
902            }
903            // mirror for generated code...
904            generated_tex_vars_t& gen = c->generated_vars.texture[i];
905            gen.width   = t.surface.width;
906            gen.height  = t.surface.height;
907            gen.stride  = t.surface.stride;
908            gen.data    = int32_t(t.surface.data);
909            gen.dsdx = ti.dsdx;
910            gen.dtdx = ti.dtdx;
911        }
912    }
913
914    // choose the y-stepper
915    c->step_y = step_y__nop;
916    if (enables & GGL_ENABLE_FOG) {
917        c->step_y = step_y__generic;
918    } else if (enables & GGL_ENABLE_TMUS) {
919        if (enables & GGL_ENABLE_SMOOTH) {
920            c->step_y = step_y__generic;
921        } else if (enables & GGL_ENABLE_W) {
922            c->step_y = step_y__w;
923        } else {
924            c->step_y = step_y__tmu;
925        }
926    } else {
927        if (enables & GGL_ENABLE_SMOOTH) {
928            c->step_y = step_y__smooth;
929        }
930    }
931
932    // choose the rectangle blitter
933    c->rect = rect_generic;
934    if ((c->step_y == step_y__nop) &&
935        (c->scanline == scanline_memcpy))
936    {
937        c->rect = rect_memcpy;
938    }
939}
940
941void init_y_packed(context_t* c, int32_t y0)
942{
943    uint8_t f = c->state.buffers.color.format;
944    c->packed = ggl_pack_color(c, f,
945            c->shade.r0, c->shade.g0, c->shade.b0, c->shade.a0);
946    c->iterators.y = y0;
947    c->step_y = step_y__nop;
948    // choose the rectangle blitter
949    c->rect = rect_generic;
950    if (c->scanline == scanline_memcpy) {
951        c->rect = rect_memcpy;
952    }
953}
954
955void init_y_noop(context_t* c, int32_t y0)
956{
957    c->iterators.y = y0;
958    c->step_y = step_y__nop;
959    // choose the rectangle blitter
960    c->rect = rect_generic;
961    if (c->scanline == scanline_memcpy) {
962        c->rect = rect_memcpy;
963    }
964}
965
966void init_y_error(context_t* c, int32_t y0)
967{
968    // woooops, shoud never happen,
969    // fail gracefully (don't display anything)
970    init_y_noop(c, y0);
971    LOGE("color-buffer has an invalid format!");
972}
973
974// ----------------------------------------------------------------------------
975#if 0
976#pragma mark -
977#endif
978
979void step_y__generic(context_t* c)
980{
981    const uint32_t enables = c->state.enables;
982
983    // iterate...
984    iterators_t& ci = c->iterators;
985    ci.y += 1;
986
987    if (enables & GGL_ENABLE_SMOOTH) {
988        ci.ydrdy += c->shade.drdy;
989        ci.ydgdy += c->shade.dgdy;
990        ci.ydbdy += c->shade.dbdy;
991        ci.ydady += c->shade.dady;
992    }
993
994    const uint32_t mask =
995            GGL_ENABLE_DEPTH_TEST |
996            GGL_ENABLE_W |
997            GGL_ENABLE_FOG;
998    if (enables & mask) {
999        ci.ydzdy += c->shade.dzdy;
1000        ci.ydwdy += c->shade.dwdy;
1001        ci.ydfdy += c->shade.dfdy;
1002    }
1003
1004    if ((enables & GGL_ENABLE_TMUS) && (!(enables & GGL_ENABLE_W))) {
1005        for (int i=0 ; i<GGL_TEXTURE_UNIT_COUNT ; ++i) {
1006            if (c->state.texture[i].enable) {
1007                texture_iterators_t& ti = c->state.texture[i].iterators;
1008                ti.ydsdy += ti.dsdy;
1009                ti.ydtdy += ti.dtdy;
1010            }
1011        }
1012    }
1013}
1014
1015void step_y__nop(context_t* c)
1016{
1017    c->iterators.y += 1;
1018    c->iterators.ydzdy += c->shade.dzdy;
1019}
1020
1021void step_y__smooth(context_t* c)
1022{
1023    iterators_t& ci = c->iterators;
1024    ci.y += 1;
1025    ci.ydrdy += c->shade.drdy;
1026    ci.ydgdy += c->shade.dgdy;
1027    ci.ydbdy += c->shade.dbdy;
1028    ci.ydady += c->shade.dady;
1029    ci.ydzdy += c->shade.dzdy;
1030}
1031
1032void step_y__w(context_t* c)
1033{
1034    iterators_t& ci = c->iterators;
1035    ci.y += 1;
1036    ci.ydzdy += c->shade.dzdy;
1037    ci.ydwdy += c->shade.dwdy;
1038}
1039
1040void step_y__tmu(context_t* c)
1041{
1042    iterators_t& ci = c->iterators;
1043    ci.y += 1;
1044    ci.ydzdy += c->shade.dzdy;
1045    for (int i=0 ; i<GGL_TEXTURE_UNIT_COUNT ; ++i) {
1046        if (c->state.texture[i].enable) {
1047            texture_iterators_t& ti = c->state.texture[i].iterators;
1048            ti.ydsdy += ti.dsdy;
1049            ti.ydtdy += ti.dtdy;
1050        }
1051    }
1052}
1053
1054// ----------------------------------------------------------------------------
1055#if 0
1056#pragma mark -
1057#endif
1058
1059void scanline_perspective(context_t* c)
1060{
1061    struct {
1062        union {
1063            struct {
1064                int32_t s, sq;
1065                int32_t t, tq;
1066            };
1067            struct {
1068                int32_t v, q;
1069            } st[2];
1070        };
1071    } tc[GGL_TEXTURE_UNIT_COUNT] __attribute__((aligned(16)));
1072
1073    // XXX: we should have a special case when dwdx = 0
1074
1075    // 32 pixels spans works okay. 16 is a lot better,
1076    // but hey, it's a software renderer...
1077    const uint32_t SPAN_BITS = 5;
1078    const uint32_t ys = c->iterators.y;
1079    const uint32_t xs = c->iterators.xl;
1080    const uint32_t x1 = c->iterators.xr;
1081	const uint32_t xc = x1 - xs;
1082    uint32_t remainder = xc & ((1<<SPAN_BITS)-1);
1083    uint32_t numSpans = xc >> SPAN_BITS;
1084
1085    const iterators_t& ci = c->iterators;
1086    int32_t w0 = (xs * c->shade.dwdx) + ci.ydwdy;
1087    int32_t q0 = gglRecipQ(w0, 30);
1088    const int iwscale = 32 - gglClz(q0);
1089
1090    const int32_t dwdx = c->shade.dwdx << SPAN_BITS;
1091    int32_t xl = c->iterators.xl;
1092
1093    // We process s & t with a loop to reduce the code size
1094    // (and i-cache pressure).
1095
1096    for (int i=0 ; i<GGL_TEXTURE_UNIT_COUNT ; ++i) {
1097        const texture_t& tmu = c->state.texture[i];
1098        if (!tmu.enable) continue;
1099        int32_t s =   tmu.shade.is0 +
1100                     (tmu.shade.idsdy * ys) + (tmu.shade.idsdx * xs) +
1101                     ((tmu.shade.idsdx + tmu.shade.idsdy)>>1);
1102        int32_t t =   tmu.shade.it0 +
1103                     (tmu.shade.idtdy * ys) + (tmu.shade.idtdx * xs) +
1104                     ((tmu.shade.idtdx + tmu.shade.idtdy)>>1);
1105        tc[i].s  = s;
1106        tc[i].t  = t;
1107        tc[i].sq = gglMulx(s, q0, iwscale);
1108        tc[i].tq = gglMulx(t, q0, iwscale);
1109    }
1110
1111    int32_t span = 0;
1112    do {
1113        int32_t w1;
1114        if (ggl_likely(numSpans)) {
1115            w1 = w0 + dwdx;
1116        } else {
1117            if (remainder) {
1118                // finish off the scanline...
1119                span = remainder;
1120                w1 = (c->shade.dwdx * span) + w0;
1121            } else {
1122                break;
1123            }
1124        }
1125        int32_t q1 = gglRecipQ(w1, 30);
1126        for (int i=0 ; i<GGL_TEXTURE_UNIT_COUNT ; ++i) {
1127            texture_t& tmu = c->state.texture[i];
1128            if (!tmu.enable) continue;
1129            texture_iterators_t& ti = tmu.iterators;
1130
1131            for (int j=0 ; j<2 ; j++) {
1132                int32_t v = tc[i].st[j].v;
1133                if (span)   v += (tmu.shade.st[j].dx)*span;
1134                else        v += (tmu.shade.st[j].dx)<<SPAN_BITS;
1135                const int32_t v0 = tc[i].st[j].q;
1136                const int32_t v1 = gglMulx(v, q1, iwscale);
1137                int32_t dvdx = v1 - v0;
1138                if (span)   dvdx /= span;
1139                else        dvdx >>= SPAN_BITS;
1140                tc[i].st[j].v = v;
1141                tc[i].st[j].q = v1;
1142
1143                const int scale = ti.st[j].scale + (iwscale - 30);
1144                if (scale >= 0) {
1145                    ti.st[j].ydvdy = v0   << scale;
1146                    ti.st[j].dvdx  = dvdx << scale;
1147                } else {
1148                    ti.st[j].ydvdy = v0   >> -scale;
1149                    ti.st[j].dvdx  = dvdx >> -scale;
1150                }
1151            }
1152            generated_tex_vars_t& gen = c->generated_vars.texture[i];
1153            gen.dsdx = ti.st[0].dvdx;
1154            gen.dtdx = ti.st[1].dvdx;
1155        }
1156        c->iterators.xl = xl;
1157        c->iterators.xr = xl = xl + (span ? span : (1<<SPAN_BITS));
1158        w0 = w1;
1159        q0 = q1;
1160        c->span(c);
1161    } while(numSpans--);
1162}
1163
1164void scanline_perspective_single(context_t* c)
1165{
1166    // 32 pixels spans works okay. 16 is a lot better,
1167    // but hey, it's a software renderer...
1168    const uint32_t SPAN_BITS = 5;
1169    const uint32_t ys = c->iterators.y;
1170    const uint32_t xs = c->iterators.xl;
1171    const uint32_t x1 = c->iterators.xr;
1172	const uint32_t xc = x1 - xs;
1173
1174    const iterators_t& ci = c->iterators;
1175    int32_t w = (xs * c->shade.dwdx) + ci.ydwdy;
1176    int32_t iw = gglRecipQ(w, 30);
1177    const int iwscale = 32 - gglClz(iw);
1178
1179    const int i = 31 - gglClz(c->state.enabled_tmu);
1180    generated_tex_vars_t& gen = c->generated_vars.texture[i];
1181    texture_t& tmu = c->state.texture[i];
1182    texture_iterators_t& ti = tmu.iterators;
1183    const int sscale = ti.sscale + (iwscale - 30);
1184    const int tscale = ti.tscale + (iwscale - 30);
1185    int32_t s =   tmu.shade.is0 +
1186                 (tmu.shade.idsdy * ys) + (tmu.shade.idsdx * xs) +
1187                 ((tmu.shade.idsdx + tmu.shade.idsdy)>>1);
1188    int32_t t =   tmu.shade.it0 +
1189                 (tmu.shade.idtdy * ys) + (tmu.shade.idtdx * xs) +
1190                 ((tmu.shade.idtdx + tmu.shade.idtdy)>>1);
1191    int32_t s0 = gglMulx(s, iw, iwscale);
1192    int32_t t0 = gglMulx(t, iw, iwscale);
1193    int32_t xl = c->iterators.xl;
1194
1195    int32_t sq, tq, dsdx, dtdx;
1196    int32_t premainder = xc & ((1<<SPAN_BITS)-1);
1197    uint32_t numSpans = xc >> SPAN_BITS;
1198    if (c->shade.dwdx == 0) {
1199        // XXX: we could choose to do this if the error is small enough
1200        numSpans = 0;
1201        premainder = xc;
1202        goto no_perspective;
1203    }
1204
1205    if (premainder) {
1206        w += c->shade.dwdx   * premainder;
1207        iw = gglRecipQ(w, 30);
1208no_perspective:
1209        s += tmu.shade.idsdx * premainder;
1210        t += tmu.shade.idtdx * premainder;
1211        sq = gglMulx(s, iw, iwscale);
1212        tq = gglMulx(t, iw, iwscale);
1213        dsdx = (sq - s0) / premainder;
1214        dtdx = (tq - t0) / premainder;
1215        c->iterators.xl = xl;
1216        c->iterators.xr = xl = xl + premainder;
1217        goto finish;
1218    }
1219
1220    while (numSpans--) {
1221        w += c->shade.dwdx   << SPAN_BITS;
1222        s += tmu.shade.idsdx << SPAN_BITS;
1223        t += tmu.shade.idtdx << SPAN_BITS;
1224        iw = gglRecipQ(w, 30);
1225        sq = gglMulx(s, iw, iwscale);
1226        tq = gglMulx(t, iw, iwscale);
1227        dsdx = (sq - s0) >> SPAN_BITS;
1228        dtdx = (tq - t0) >> SPAN_BITS;
1229        c->iterators.xl = xl;
1230        c->iterators.xr = xl = xl + (1<<SPAN_BITS);
1231finish:
1232        if (sscale >= 0) {
1233            ti.ydsdy = s0   << sscale;
1234            ti.dsdx  = dsdx << sscale;
1235        } else {
1236            ti.ydsdy = s0   >>-sscale;
1237            ti.dsdx  = dsdx >>-sscale;
1238        }
1239        if (tscale >= 0) {
1240            ti.ydtdy = t0   << tscale;
1241            ti.dtdx  = dtdx << tscale;
1242        } else {
1243            ti.ydtdy = t0   >>-tscale;
1244            ti.dtdx  = dtdx >>-tscale;
1245        }
1246        s0 = sq;
1247        t0 = tq;
1248        gen.dsdx = ti.dsdx;
1249        gen.dtdx = ti.dtdx;
1250        c->span(c);
1251    }
1252}
1253
1254// ----------------------------------------------------------------------------
1255
1256void scanline_t32cb16(context_t* c)
1257{
1258    int32_t x = c->iterators.xl;
1259    size_t ct = c->iterators.xr - x;
1260    int32_t y = c->iterators.y;
1261    surface_t* cb = &(c->state.buffers.color);
1262    union {
1263        uint16_t* dst;
1264        uint32_t* dst32;
1265    };
1266    dst = reinterpret_cast<uint16_t*>(cb->data) + (x+(cb->stride*y));
1267
1268    surface_t* tex = &(c->state.texture[0].surface);
1269    const int32_t u = (c->state.texture[0].shade.is0>>16) + x;
1270    const int32_t v = (c->state.texture[0].shade.it0>>16) + y;
1271    uint32_t *src = reinterpret_cast<uint32_t*>(tex->data)+(u+(tex->stride*v));
1272    int sR, sG, sB;
1273    uint32_t s, d;
1274
1275    if (ct==1 || uint32_t(dst)&2) {
1276last_one:
1277        s = GGL_RGBA_TO_HOST( *src++ );
1278        sR = (s >> (   3))&0x1F;
1279        sG = (s >> ( 8+2))&0x3F;
1280        sB = (s >> (16+3))&0x1F;
1281        *dst++ = uint16_t((sR<<11)|(sG<<5)|sB);
1282        ct--;
1283    }
1284
1285    while (ct >= 2) {
1286        s = GGL_RGBA_TO_HOST( *src++ );
1287        sR = (s >> (   3))&0x1F;
1288        sG = (s >> ( 8+2))&0x3F;
1289        sB = (s >> (16+3))&0x1F;
1290        d = (sR<<11)|(sG<<5)|sB;
1291
1292        s = GGL_RGBA_TO_HOST( *src++ );
1293        sR = (s >> (   3))&0x1F;
1294        sG = (s >> ( 8+2))&0x3F;
1295        sB = (s >> (16+3))&0x1F;
1296        d |= ((sR<<11)|(sG<<5)|sB)<<16;
1297
1298#if BYTE_ORDER == BIG_ENDIAN
1299        d = (d>>16) | (d<<16);
1300#endif
1301
1302        *dst32++ = d;
1303        ct -= 2;
1304    }
1305
1306    if (ct > 0) {
1307        goto last_one;
1308    }
1309}
1310
1311void scanline_t32cb16blend(context_t* c)
1312{
1313    int32_t x = c->iterators.xl;
1314    size_t ct = c->iterators.xr - x;
1315    int32_t y = c->iterators.y;
1316    surface_t* cb = &(c->state.buffers.color);
1317    uint16_t* dst = reinterpret_cast<uint16_t*>(cb->data) + (x+(cb->stride*y));
1318
1319    surface_t* tex = &(c->state.texture[0].surface);
1320    const int32_t u = (c->state.texture[0].shade.is0>>16) + x;
1321    const int32_t v = (c->state.texture[0].shade.it0>>16) + y;
1322    uint32_t *src = reinterpret_cast<uint32_t*>(tex->data)+(u+(tex->stride*v));
1323
1324#if ((ANDROID_CODEGEN >= ANDROID_CODEGEN_ASM) && defined(__arm__))
1325    scanline_t32cb16blend_arm(dst, src, ct);
1326#else
1327    while (ct--) {
1328        uint32_t s = *src++;
1329        if (!s) {
1330            dst++;
1331            continue;
1332        }
1333        uint16_t d = *dst;
1334        s = GGL_RGBA_TO_HOST(s);
1335        int sR = (s >> (   3))&0x1F;
1336        int sG = (s >> ( 8+2))&0x3F;
1337        int sB = (s >> (16+3))&0x1F;
1338        int sA = (s>>24);
1339        int f = 0x100 - (sA + (sA>>7));
1340        int dR = (d>>11)&0x1f;
1341        int dG = (d>>5)&0x3f;
1342        int dB = (d)&0x1f;
1343        sR += (f*dR)>>8;
1344        sG += (f*dG)>>8;
1345        sB += (f*dB)>>8;
1346        *dst++ = uint16_t((sR<<11)|(sG<<5)|sB);
1347    }
1348#endif
1349}
1350
1351void scanline_memcpy(context_t* c)
1352{
1353    int32_t x = c->iterators.xl;
1354    size_t ct = c->iterators.xr - x;
1355    int32_t y = c->iterators.y;
1356    surface_t* cb = &(c->state.buffers.color);
1357    const GGLFormat* fp = &(c->formats[cb->format]);
1358    uint8_t* dst = reinterpret_cast<uint8_t*>(cb->data) +
1359                            (x + (cb->stride * y)) * fp->size;
1360
1361    surface_t* tex = &(c->state.texture[0].surface);
1362    const int32_t u = (c->state.texture[0].shade.is0>>16) + x;
1363    const int32_t v = (c->state.texture[0].shade.it0>>16) + y;
1364    uint8_t *src = reinterpret_cast<uint8_t*>(tex->data) +
1365                            (u + (tex->stride * v)) * fp->size;
1366
1367    const size_t size = ct * fp->size;
1368    memcpy(dst, src, size);
1369}
1370
1371void scanline_memset8(context_t* c)
1372{
1373    int32_t x = c->iterators.xl;
1374    size_t ct = c->iterators.xr - x;
1375    int32_t y = c->iterators.y;
1376    surface_t* cb = &(c->state.buffers.color);
1377    uint8_t* dst = reinterpret_cast<uint8_t*>(cb->data) + (x+(cb->stride*y));
1378    uint32_t packed = c->packed;
1379    memset(dst, packed, ct);
1380}
1381
1382void scanline_memset16(context_t* c)
1383{
1384    int32_t x = c->iterators.xl;
1385    size_t ct = c->iterators.xr - x;
1386    int32_t y = c->iterators.y;
1387    surface_t* cb = &(c->state.buffers.color);
1388    uint16_t* dst = reinterpret_cast<uint16_t*>(cb->data) + (x+(cb->stride*y));
1389    uint32_t packed = c->packed;
1390    android_memset16(dst, packed, ct*2);
1391}
1392
1393void scanline_memset32(context_t* c)
1394{
1395    int32_t x = c->iterators.xl;
1396    size_t ct = c->iterators.xr - x;
1397    int32_t y = c->iterators.y;
1398    surface_t* cb = &(c->state.buffers.color);
1399    uint32_t* dst = reinterpret_cast<uint32_t*>(cb->data) + (x+(cb->stride*y));
1400    uint32_t packed = GGL_HOST_TO_RGBA(c->packed);
1401    android_memset32(dst, packed, ct*4);
1402}
1403
1404void scanline_clear(context_t* c)
1405{
1406    int32_t x = c->iterators.xl;
1407    size_t ct = c->iterators.xr - x;
1408    int32_t y = c->iterators.y;
1409    surface_t* cb = &(c->state.buffers.color);
1410    const GGLFormat* fp = &(c->formats[cb->format]);
1411    uint8_t* dst = reinterpret_cast<uint8_t*>(cb->data) +
1412                            (x + (cb->stride * y)) * fp->size;
1413    const size_t size = ct * fp->size;
1414    memset(dst, 0, size);
1415}
1416
1417void scanline_set(context_t* c)
1418{
1419    int32_t x = c->iterators.xl;
1420    size_t ct = c->iterators.xr - x;
1421    int32_t y = c->iterators.y;
1422    surface_t* cb = &(c->state.buffers.color);
1423    const GGLFormat* fp = &(c->formats[cb->format]);
1424    uint8_t* dst = reinterpret_cast<uint8_t*>(cb->data) +
1425                            (x + (cb->stride * y)) * fp->size;
1426    const size_t size = ct * fp->size;
1427    memset(dst, 0xFF, size);
1428}
1429
1430void scanline_noop(context_t* c)
1431{
1432}
1433
1434void rect_generic(context_t* c, size_t yc)
1435{
1436    do {
1437        c->scanline(c);
1438        c->step_y(c);
1439    } while (--yc);
1440}
1441
1442void rect_memcpy(context_t* c, size_t yc)
1443{
1444    int32_t x = c->iterators.xl;
1445    size_t ct = c->iterators.xr - x;
1446    int32_t y = c->iterators.y;
1447    surface_t* cb = &(c->state.buffers.color);
1448    const GGLFormat* fp = &(c->formats[cb->format]);
1449    uint8_t* dst = reinterpret_cast<uint8_t*>(cb->data) +
1450                            (x + (cb->stride * y)) * fp->size;
1451
1452    surface_t* tex = &(c->state.texture[0].surface);
1453    const int32_t u = (c->state.texture[0].shade.is0>>16) + x;
1454    const int32_t v = (c->state.texture[0].shade.it0>>16) + y;
1455    uint8_t *src = reinterpret_cast<uint8_t*>(tex->data) +
1456                            (u + (tex->stride * v)) * fp->size;
1457
1458    if (cb->stride == tex->stride && ct == size_t(cb->stride)) {
1459        memcpy(dst, src, ct * fp->size * yc);
1460    } else {
1461        const size_t size = ct * fp->size;
1462        const size_t dbpr = cb->stride  * fp->size;
1463        const size_t sbpr = tex->stride * fp->size;
1464        do {
1465            memcpy(dst, src, size);
1466            dst += dbpr;
1467            src += sbpr;
1468        } while (--yc);
1469    }
1470}
1471// ----------------------------------------------------------------------------
1472}; // namespace android
1473
1474using namespace android;
1475extern "C" void ggl_test_codegen(uint32_t n, uint32_t p, uint32_t t0, uint32_t t1)
1476{
1477#if ANDROID_ARM_CODEGEN
1478    GGLContext* c;
1479    gglInit(&c);
1480    needs_t needs;
1481    needs.n = n;
1482    needs.p = p;
1483    needs.t[0] = t0;
1484    needs.t[1] = t1;
1485    sp<ScanlineAssembly> a(new ScanlineAssembly(needs, ASSEMBLY_SCRATCH_SIZE));
1486    GGLAssembler assembler( new ARMAssembler(a) );
1487    int err = assembler.scanline(needs, (context_t*)c);
1488    if (err != 0) {
1489        printf("error %08x (%s)\n", err, strerror(-err));
1490    }
1491    gglUninit(c);
1492#else
1493    printf("This test runs only on ARM\n");
1494#endif
1495}
1496
1497