vg_context.c revision f914cd1796845164109c837a111c39ba64852ad4
1/**************************************************************************
2 *
3 * Copyright 2009 VMware, Inc.  All Rights Reserved.
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining a
6 * copy of this software and associated documentation files (the
7 * "Software"), to deal in the Software without restriction, including
8 * without limitation the rights to use, copy, modify, merge, publish,
9 * distribute, sub license, and/or sell copies of the Software, and to
10 * permit persons to whom the Software is furnished to do so, subject to
11 * the following conditions:
12 *
13 * The above copyright notice and this permission notice (including the
14 * next paragraph) shall be included in all copies or substantial portions
15 * of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
18 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
19 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
20 * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
21 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
22 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
23 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
24 *
25 **************************************************************************/
26
27#include "vg_context.h"
28
29#include "paint.h"
30#include "renderer.h"
31#include "shaders_cache.h"
32#include "shader.h"
33#include "asm_util.h"
34#include "st_inlines.h"
35#include "vg_manager.h"
36#include "api.h"
37
38#include "pipe/p_context.h"
39#include "util/u_inlines.h"
40#include "pipe/p_shader_tokens.h"
41
42#include "cso_cache/cso_context.h"
43
44#include "util/u_simple_shaders.h"
45#include "util/u_memory.h"
46#include "util/u_blit.h"
47#include "util/u_sampler.h"
48
49struct vg_context *_vg_context = 0;
50
51struct vg_context * vg_current_context(void)
52{
53   return _vg_context;
54}
55
56static void init_clear(struct vg_context *st)
57{
58   struct pipe_context *pipe = st->pipe;
59
60   /* rasterizer state: bypass clipping */
61   memset(&st->clear.raster, 0, sizeof(st->clear.raster));
62   st->clear.raster.gl_rasterization_rules = 1;
63
64   /* fragment shader state: color pass-through program */
65   st->clear.fs =
66      util_make_fragment_passthrough_shader(pipe);
67}
68
69/**
70 * A depth/stencil rb will be needed regardless of what the visual says.
71 */
72static boolean
73choose_depth_stencil_format(struct vg_context *ctx)
74{
75   struct pipe_screen *screen = ctx->pipe->screen;
76   enum pipe_format formats[] = {
77      PIPE_FORMAT_Z24_UNORM_S8_USCALED,
78      PIPE_FORMAT_S8_USCALED_Z24_UNORM,
79      PIPE_FORMAT_NONE
80   };
81   enum pipe_format *fmt;
82
83   for (fmt = formats; *fmt != PIPE_FORMAT_NONE; fmt++) {
84      if (screen->is_format_supported(screen, *fmt,
85               PIPE_TEXTURE_2D, 0, PIPE_BIND_DEPTH_STENCIL, 0))
86         break;
87   }
88
89   ctx->ds_format = *fmt;
90
91   return (ctx->ds_format != PIPE_FORMAT_NONE);
92}
93
94void vg_set_current_context(struct vg_context *ctx)
95{
96   _vg_context = ctx;
97   api_make_dispatch_current((ctx) ? ctx->dispatch : NULL);
98}
99
100struct vg_context * vg_create_context(struct pipe_context *pipe,
101                                      const void *visual,
102                                      struct vg_context *share)
103{
104   struct vg_context *ctx;
105   unsigned i;
106
107   ctx = CALLOC_STRUCT(vg_context);
108
109   ctx->pipe = pipe;
110   if (!choose_depth_stencil_format(ctx)) {
111      FREE(ctx);
112      return NULL;
113   }
114
115   ctx->dispatch = api_create_dispatch();
116
117   vg_init_state(&ctx->state.vg);
118   ctx->state.dirty = ALL_DIRTY;
119
120   ctx->cso_context = cso_create_context(pipe);
121
122   init_clear(ctx);
123
124   ctx->default_paint = paint_create(ctx);
125   ctx->state.vg.stroke_paint = ctx->default_paint;
126   ctx->state.vg.fill_paint = ctx->default_paint;
127
128
129   ctx->mask.sampler.wrap_s = PIPE_TEX_WRAP_CLAMP_TO_EDGE;
130   ctx->mask.sampler.wrap_t = PIPE_TEX_WRAP_CLAMP_TO_EDGE;
131   ctx->mask.sampler.min_mip_filter = PIPE_TEX_MIPFILTER_NONE;
132   ctx->mask.sampler.min_img_filter = PIPE_TEX_FILTER_NEAREST;
133   ctx->mask.sampler.mag_img_filter = PIPE_TEX_FILTER_NEAREST;
134   ctx->mask.sampler.normalized_coords = 0;
135
136   ctx->blend_sampler.wrap_s = PIPE_TEX_WRAP_CLAMP_TO_EDGE;
137   ctx->blend_sampler.wrap_t = PIPE_TEX_WRAP_CLAMP_TO_EDGE;
138   ctx->blend_sampler.min_mip_filter = PIPE_TEX_MIPFILTER_NONE;
139   ctx->blend_sampler.min_img_filter = PIPE_TEX_FILTER_NEAREST;
140   ctx->blend_sampler.mag_img_filter = PIPE_TEX_FILTER_NEAREST;
141   ctx->blend_sampler.normalized_coords = 0;
142
143   for (i = 0; i < 2; i++) {
144      ctx->velems[i].src_offset = i * 4 * sizeof(float);
145      ctx->velems[i].instance_divisor = 0;
146      ctx->velems[i].vertex_buffer_index = 0;
147      ctx->velems[i].src_format = PIPE_FORMAT_R32G32B32A32_FLOAT;
148   }
149
150   vg_set_error(ctx, VG_NO_ERROR);
151
152   ctx->owned_objects[VG_OBJECT_PAINT] = cso_hash_create();
153   ctx->owned_objects[VG_OBJECT_IMAGE] = cso_hash_create();
154   ctx->owned_objects[VG_OBJECT_MASK] = cso_hash_create();
155   ctx->owned_objects[VG_OBJECT_FONT] = cso_hash_create();
156   ctx->owned_objects[VG_OBJECT_PATH] = cso_hash_create();
157
158   ctx->renderer = renderer_create(ctx);
159   ctx->sc = shaders_cache_create(ctx);
160   ctx->shader = shader_create(ctx);
161
162   ctx->blit = util_create_blit(ctx->pipe, ctx->cso_context);
163
164   return ctx;
165}
166
167void vg_destroy_context(struct vg_context *ctx)
168{
169   struct pipe_resource **cbuf = &ctx->mask.cbuf;
170   struct pipe_resource **vsbuf = &ctx->vs_const_buffer;
171
172   util_destroy_blit(ctx->blit);
173   renderer_destroy(ctx->renderer);
174   shaders_cache_destroy(ctx->sc);
175   shader_destroy(ctx->shader);
176   paint_destroy(ctx->default_paint);
177
178   if (*cbuf)
179      pipe_resource_reference(cbuf, NULL);
180
181   if (*vsbuf)
182      pipe_resource_reference(vsbuf, NULL);
183
184   if (ctx->clear.fs) {
185      cso_delete_fragment_shader(ctx->cso_context, ctx->clear.fs);
186      ctx->clear.fs = NULL;
187   }
188
189   if (ctx->plain_vs) {
190      vg_shader_destroy(ctx, ctx->plain_vs);
191      ctx->plain_vs = NULL;
192   }
193   if (ctx->clear_vs) {
194      vg_shader_destroy(ctx, ctx->clear_vs);
195      ctx->clear_vs = NULL;
196   }
197   if (ctx->texture_vs) {
198      vg_shader_destroy(ctx, ctx->texture_vs);
199      ctx->texture_vs = NULL;
200   }
201
202   if (ctx->pass_through_depth_fs)
203      vg_shader_destroy(ctx, ctx->pass_through_depth_fs);
204   if (ctx->mask.union_fs)
205      vg_shader_destroy(ctx, ctx->mask.union_fs);
206   if (ctx->mask.intersect_fs)
207      vg_shader_destroy(ctx, ctx->mask.intersect_fs);
208   if (ctx->mask.subtract_fs)
209      vg_shader_destroy(ctx, ctx->mask.subtract_fs);
210   if (ctx->mask.set_fs)
211      vg_shader_destroy(ctx, ctx->mask.set_fs);
212
213   cso_release_all(ctx->cso_context);
214   cso_destroy_context(ctx->cso_context);
215
216   cso_hash_delete(ctx->owned_objects[VG_OBJECT_PAINT]);
217   cso_hash_delete(ctx->owned_objects[VG_OBJECT_IMAGE]);
218   cso_hash_delete(ctx->owned_objects[VG_OBJECT_MASK]);
219   cso_hash_delete(ctx->owned_objects[VG_OBJECT_FONT]);
220   cso_hash_delete(ctx->owned_objects[VG_OBJECT_PATH]);
221
222   api_destroy_dispatch(ctx->dispatch);
223
224   FREE(ctx);
225}
226
227void vg_init_object(struct vg_object *obj, struct vg_context *ctx, enum vg_object_type type)
228{
229   obj->type = type;
230   obj->ctx = ctx;
231}
232
233VGboolean vg_context_is_object_valid(struct vg_context *ctx,
234                                enum vg_object_type type,
235                                void *ptr)
236{
237    if (ctx) {
238       struct cso_hash *hash = ctx->owned_objects[type];
239       if (!hash)
240          return VG_FALSE;
241       return cso_hash_contains(hash, (unsigned)(long)ptr);
242    }
243    return VG_FALSE;
244}
245
246void vg_context_add_object(struct vg_context *ctx,
247                           enum vg_object_type type,
248                           void *ptr)
249{
250    if (ctx) {
251       struct cso_hash *hash = ctx->owned_objects[type];
252       if (!hash)
253          return;
254       cso_hash_insert(hash, (unsigned)(long)ptr, ptr);
255    }
256}
257
258void vg_context_remove_object(struct vg_context *ctx,
259                              enum vg_object_type type,
260                              void *ptr)
261{
262   if (ctx) {
263      struct cso_hash *hash = ctx->owned_objects[type];
264      if (!hash)
265         return;
266      cso_hash_take(hash, (unsigned)(long)ptr);
267   }
268}
269
270static void update_clip_state(struct vg_context *ctx)
271{
272   struct pipe_depth_stencil_alpha_state *dsa = &ctx->state.g3d.dsa;
273   struct vg_state *state =  &ctx->state.vg;
274
275   memset(dsa, 0, sizeof(struct pipe_depth_stencil_alpha_state));
276
277   if (state->scissoring) {
278      struct pipe_blend_state *blend = &ctx->state.g3d.blend;
279      struct pipe_framebuffer_state *fb = &ctx->state.g3d.fb;
280      int i;
281
282      dsa->depth.writemask = 1;/*glDepthMask(TRUE);*/
283      dsa->depth.func = PIPE_FUNC_ALWAYS;
284      dsa->depth.enabled = 1;
285
286      cso_save_blend(ctx->cso_context);
287      cso_save_fragment_shader(ctx->cso_context);
288      /* set a passthrough shader */
289      if (!ctx->pass_through_depth_fs)
290         ctx->pass_through_depth_fs = shader_create_from_text(ctx->pipe,
291                                                              pass_through_depth_asm,
292                                                              40,
293                                                              PIPE_SHADER_FRAGMENT);
294      cso_set_fragment_shader_handle(ctx->cso_context,
295                                     ctx->pass_through_depth_fs->driver);
296      cso_set_depth_stencil_alpha(ctx->cso_context, dsa);
297
298      ctx->pipe->clear(ctx->pipe, PIPE_CLEAR_DEPTHSTENCIL, NULL, 1.0, 0);
299
300      /* disable color writes */
301      blend->rt[0].colormask = 0; /*disable colorwrites*/
302      cso_set_blend(ctx->cso_context, blend);
303
304      /* enable scissoring */
305      for (i = 0; i < state->scissor_rects_num; ++i) {
306         const float x      = state->scissor_rects[i * 4 + 0].f;
307         const float y      = state->scissor_rects[i * 4 + 1].f;
308         const float width  = state->scissor_rects[i * 4 + 2].f;
309         const float height = state->scissor_rects[i * 4 + 3].f;
310         VGfloat minx, miny, maxx, maxy;
311
312         minx = 0;
313         miny = 0;
314         maxx = fb->width;
315         maxy = fb->height;
316
317         if (x > minx)
318            minx = x;
319         if (y > miny)
320            miny = y;
321
322         if (x + width < maxx)
323            maxx = x + width;
324         if (y + height < maxy)
325            maxy = y + height;
326
327         /* check for null space */
328         if (minx >= maxx || miny >= maxy)
329            minx = miny = maxx = maxy = 0;
330
331         /*glClear(GL_DEPTH_BUFFER_BIT);*/
332         renderer_draw_quad(ctx->renderer, minx, miny, maxx, maxy, 0.0f);
333      }
334
335      cso_restore_blend(ctx->cso_context);
336      cso_restore_fragment_shader(ctx->cso_context);
337
338      dsa->depth.enabled = 1; /* glEnable(GL_DEPTH_TEST); */
339      dsa->depth.writemask = 0;/*glDepthMask(FALSE);*/
340      dsa->depth.func = PIPE_FUNC_GEQUAL;
341   }
342}
343
344void vg_validate_state(struct vg_context *ctx)
345{
346   vg_manager_validate_framebuffer(ctx);
347
348   if ((ctx->state.dirty & BLEND_DIRTY)) {
349      struct pipe_blend_state *blend = &ctx->state.g3d.blend;
350      memset(blend, 0, sizeof(struct pipe_blend_state));
351      blend->rt[0].blend_enable = 1;
352      blend->rt[0].colormask = PIPE_MASK_RGBA;
353
354      switch (ctx->state.vg.blend_mode) {
355      case VG_BLEND_SRC:
356         blend->rt[0].rgb_src_factor   = PIPE_BLENDFACTOR_ONE;
357         blend->rt[0].alpha_src_factor = PIPE_BLENDFACTOR_ONE;
358         blend->rt[0].rgb_dst_factor   = PIPE_BLENDFACTOR_ZERO;
359         blend->rt[0].alpha_dst_factor = PIPE_BLENDFACTOR_ZERO;
360         blend->rt[0].blend_enable = 0;
361         break;
362      case VG_BLEND_SRC_OVER:
363         blend->rt[0].rgb_src_factor   = PIPE_BLENDFACTOR_SRC_ALPHA;
364         blend->rt[0].alpha_src_factor = PIPE_BLENDFACTOR_ONE;
365         blend->rt[0].rgb_dst_factor   = PIPE_BLENDFACTOR_INV_SRC_ALPHA;
366         blend->rt[0].alpha_dst_factor = PIPE_BLENDFACTOR_INV_SRC_ALPHA;
367         break;
368      case VG_BLEND_DST_OVER:
369         blend->rt[0].rgb_src_factor   = PIPE_BLENDFACTOR_INV_DST_ALPHA;
370         blend->rt[0].alpha_src_factor = PIPE_BLENDFACTOR_INV_DST_ALPHA;
371         blend->rt[0].rgb_dst_factor   = PIPE_BLENDFACTOR_DST_ALPHA;
372         blend->rt[0].alpha_dst_factor = PIPE_BLENDFACTOR_DST_ALPHA;
373         break;
374      case VG_BLEND_SRC_IN:
375         blend->rt[0].rgb_src_factor   = PIPE_BLENDFACTOR_DST_ALPHA;
376         blend->rt[0].alpha_src_factor = PIPE_BLENDFACTOR_DST_ALPHA;
377         blend->rt[0].rgb_dst_factor   = PIPE_BLENDFACTOR_ZERO;
378         blend->rt[0].alpha_dst_factor = PIPE_BLENDFACTOR_ZERO;
379         break;
380      case VG_BLEND_DST_IN:
381         blend->rt[0].rgb_src_factor   = PIPE_BLENDFACTOR_ZERO;
382         blend->rt[0].alpha_src_factor = PIPE_BLENDFACTOR_ZERO;
383         blend->rt[0].rgb_dst_factor   = PIPE_BLENDFACTOR_SRC_ALPHA;
384         blend->rt[0].alpha_dst_factor = PIPE_BLENDFACTOR_SRC_ALPHA;
385         break;
386      case VG_BLEND_MULTIPLY:
387      case VG_BLEND_SCREEN:
388      case VG_BLEND_DARKEN:
389      case VG_BLEND_LIGHTEN:
390         blend->rt[0].rgb_src_factor   = PIPE_BLENDFACTOR_ONE;
391         blend->rt[0].alpha_src_factor = PIPE_BLENDFACTOR_ONE;
392         blend->rt[0].rgb_dst_factor   = PIPE_BLENDFACTOR_ZERO;
393         blend->rt[0].alpha_dst_factor = PIPE_BLENDFACTOR_ZERO;
394         blend->rt[0].blend_enable = 0;
395         break;
396      case VG_BLEND_ADDITIVE:
397         blend->rt[0].rgb_src_factor   = PIPE_BLENDFACTOR_ONE;
398         blend->rt[0].alpha_src_factor = PIPE_BLENDFACTOR_ONE;
399         blend->rt[0].rgb_dst_factor   = PIPE_BLENDFACTOR_ONE;
400         blend->rt[0].alpha_dst_factor = PIPE_BLENDFACTOR_ONE;
401         break;
402      default:
403         assert(!"not implemented blend mode");
404      }
405      cso_set_blend(ctx->cso_context, &ctx->state.g3d.blend);
406   }
407   if ((ctx->state.dirty & RASTERIZER_DIRTY)) {
408      struct pipe_rasterizer_state *raster = &ctx->state.g3d.rasterizer;
409      memset(raster, 0, sizeof(struct pipe_rasterizer_state));
410      raster->gl_rasterization_rules = 1;
411      cso_set_rasterizer(ctx->cso_context, &ctx->state.g3d.rasterizer);
412   }
413   if ((ctx->state.dirty & VIEWPORT_DIRTY)) {
414      struct pipe_framebuffer_state *fb = &ctx->state.g3d.fb;
415      const VGint param_bytes = 8 * sizeof(VGfloat);
416      VGfloat vs_consts[8] = {
417         2.f/fb->width, 2.f/fb->height, 1, 1,
418         -1, -1, 0, 0
419      };
420      struct pipe_resource **cbuf = &ctx->vs_const_buffer;
421
422      vg_set_viewport(ctx, VEGA_Y0_BOTTOM);
423
424      pipe_resource_reference(cbuf, NULL);
425      *cbuf = pipe_buffer_create(ctx->pipe->screen,
426				 PIPE_BIND_CONSTANT_BUFFER,
427				 param_bytes);
428
429      if (*cbuf) {
430         st_no_flush_pipe_buffer_write(ctx, *cbuf,
431                                       0, param_bytes, vs_consts);
432      }
433      ctx->pipe->set_constant_buffer(ctx->pipe, PIPE_SHADER_VERTEX, 0, *cbuf);
434   }
435   if ((ctx->state.dirty & VS_DIRTY)) {
436      cso_set_vertex_shader_handle(ctx->cso_context,
437                                   vg_plain_vs(ctx));
438   }
439
440   /* must be last because it renders to the depth buffer*/
441   if ((ctx->state.dirty & DEPTH_STENCIL_DIRTY)) {
442      update_clip_state(ctx);
443      cso_set_depth_stencil_alpha(ctx->cso_context, &ctx->state.g3d.dsa);
444   }
445
446   shader_set_masking(ctx->shader, ctx->state.vg.masking);
447   shader_set_image_mode(ctx->shader, ctx->state.vg.image_mode);
448
449   ctx->state.dirty = NONE_DIRTY;
450}
451
452VGboolean vg_object_is_valid(void *ptr, enum vg_object_type type)
453{
454   struct vg_object *obj = ptr;
455   if (ptr && is_aligned(obj) && obj->type == type)
456      return VG_TRUE;
457   else
458      return VG_FALSE;
459}
460
461void vg_set_error(struct vg_context *ctx,
462                  VGErrorCode code)
463{
464   /*vgGetError returns the oldest error code provided by
465    * an API call on the current context since the previous
466    * call to vgGetError on that context (or since the creation
467    of the context).*/
468   if (ctx->_error == VG_NO_ERROR)
469      ctx->_error = code;
470}
471
472void vg_prepare_blend_surface(struct vg_context *ctx)
473{
474   struct pipe_surface *dest_surface = NULL;
475   struct pipe_context *pipe = ctx->pipe;
476   struct pipe_sampler_view *view;
477   struct pipe_sampler_view view_templ;
478   struct st_framebuffer *stfb = ctx->draw_buffer;
479   struct st_renderbuffer *strb = stfb->strb;
480
481   /* first finish all pending rendering */
482   vgFinish();
483
484   u_sampler_view_default_template(&view_templ, strb->texture, strb->texture->format);
485   view = pipe->create_sampler_view(pipe, strb->texture, &view_templ);
486
487   dest_surface = pipe->screen->get_tex_surface(pipe->screen,
488                                                stfb->blend_texture_view->texture,
489                                                0, 0, 0,
490                                                PIPE_BIND_RENDER_TARGET);
491   /* flip it, because we want to use it as a sampler */
492   util_blit_pixels_tex(ctx->blit,
493                        view,
494                        0, strb->height,
495                        strb->width, 0,
496                        dest_surface,
497                        0, 0,
498                        strb->width, strb->height,
499                        0.0, PIPE_TEX_MIPFILTER_NEAREST);
500
501   if (dest_surface)
502      pipe_surface_reference(&dest_surface, NULL);
503
504   /* make sure it's complete */
505   vgFinish();
506
507   pipe_sampler_view_reference(&view, NULL);
508}
509
510
511void vg_prepare_blend_surface_from_mask(struct vg_context *ctx)
512{
513   struct pipe_surface *dest_surface = NULL;
514   struct pipe_context *pipe = ctx->pipe;
515   struct st_framebuffer *stfb = ctx->draw_buffer;
516   struct st_renderbuffer *strb = stfb->strb;
517
518   vg_validate_state(ctx);
519
520   /* first finish all pending rendering */
521   vgFinish();
522
523   dest_surface = pipe->screen->get_tex_surface(pipe->screen,
524                                                stfb->blend_texture_view->texture,
525                                                0, 0, 0,
526                                                PIPE_BIND_RENDER_TARGET);
527
528   /* flip it, because we want to use it as a sampler */
529   util_blit_pixels_tex(ctx->blit,
530                        stfb->alpha_mask_view,
531                        0, strb->height,
532                        strb->width, 0,
533                        dest_surface,
534                        0, 0,
535                        strb->width, strb->height,
536                        0.0, PIPE_TEX_MIPFILTER_NEAREST);
537
538   /* make sure it's complete */
539   vgFinish();
540
541   if (dest_surface)
542      pipe_surface_reference(&dest_surface, NULL);
543}
544
545void * vg_plain_vs(struct vg_context *ctx)
546{
547   if (!ctx->plain_vs) {
548      ctx->plain_vs = shader_create_from_text(ctx->pipe,
549                                              vs_plain_asm,
550                                              200,
551                                              PIPE_SHADER_VERTEX);
552   }
553
554   return ctx->plain_vs->driver;
555}
556
557
558void * vg_clear_vs(struct vg_context *ctx)
559{
560   if (!ctx->clear_vs) {
561      ctx->clear_vs = shader_create_from_text(ctx->pipe,
562                                              vs_clear_asm,
563                                              200,
564                                              PIPE_SHADER_VERTEX);
565   }
566
567   return ctx->clear_vs->driver;
568}
569
570void * vg_texture_vs(struct vg_context *ctx)
571{
572   if (!ctx->texture_vs) {
573      ctx->texture_vs = shader_create_from_text(ctx->pipe,
574                                                vs_texture_asm,
575                                                200,
576                                                PIPE_SHADER_VERTEX);
577   }
578
579   return ctx->texture_vs->driver;
580}
581
582void vg_set_viewport(struct vg_context *ctx, VegaOrientation orientation)
583{
584   struct pipe_viewport_state viewport;
585   struct pipe_framebuffer_state *fb = &ctx->state.g3d.fb;
586   VGfloat y_scale = (orientation == VEGA_Y0_BOTTOM) ? -2.f : 2.f;
587
588   viewport.scale[0] =  fb->width / 2.f;
589   viewport.scale[1] =  fb->height / y_scale;
590   viewport.scale[2] =  1.0;
591   viewport.scale[3] =  1.0;
592   viewport.translate[0] = fb->width / 2.f;
593   viewport.translate[1] = fb->height / 2.f;
594   viewport.translate[2] = 0.0;
595   viewport.translate[3] = 0.0;
596
597   cso_set_viewport(ctx->cso_context, &viewport);
598}
599