1/*
2 * Mesa 3-D graphics library
3 * Version:  7.1
4 *
5 * Copyright (C) 1999-2008  Brian Paul   All Rights Reserved.
6 *
7 * Permission is hereby granted, free of charge, to any person obtaining a
8 * copy of this software and associated documentation files (the "Software"),
9 * to deal in the Software without restriction, including without limitation
10 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
11 * and/or sell copies of the Software, and to permit persons to whom the
12 * Software is furnished to do so, subject to the following conditions:
13 *
14 * The above copyright notice and this permission notice shall be included
15 * in all copies or substantial portions 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 MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
20 * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
21 * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
22 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
23 */
24
25/**
26 * \file swrast/s_bitmap.c
27 * \brief glBitmap rendering.
28 * \author Brian Paul
29 */
30
31#include "main/glheader.h"
32#include "main/bufferobj.h"
33#include "main/condrender.h"
34#include "main/image.h"
35#include "main/macros.h"
36#include "main/pbo.h"
37
38#include "s_context.h"
39#include "s_span.h"
40
41
42
43/**
44 * Render a bitmap.
45 * Called via ctx->Driver.Bitmap()
46 * All parameter error checking will have been done before this is called.
47 */
48void
49_swrast_Bitmap( struct gl_context *ctx, GLint px, GLint py,
50		GLsizei width, GLsizei height,
51		const struct gl_pixelstore_attrib *unpack,
52		const GLubyte *bitmap )
53{
54   GLint row, col;
55   GLuint count = 0;
56   SWspan span;
57
58   ASSERT(ctx->RenderMode == GL_RENDER);
59
60   if (!_mesa_check_conditional_render(ctx))
61      return; /* don't draw */
62
63   bitmap = (const GLubyte *) _mesa_map_pbo_source(ctx, unpack, bitmap);
64   if (!bitmap)
65      return;
66
67   swrast_render_start(ctx);
68
69   if (SWRAST_CONTEXT(ctx)->NewState)
70      _swrast_validate_derived( ctx );
71
72   INIT_SPAN(span, GL_BITMAP);
73   span.end = width;
74   span.arrayMask = SPAN_XY;
75   _swrast_span_default_attribs(ctx, &span);
76
77   for (row = 0; row < height; row++) {
78      const GLubyte *src = (const GLubyte *) _mesa_image_address2d(unpack,
79                 bitmap, width, height, GL_COLOR_INDEX, GL_BITMAP, row, 0);
80
81      if (unpack->LsbFirst) {
82         /* Lsb first */
83         GLubyte mask = 1U << (unpack->SkipPixels & 0x7);
84         for (col = 0; col < width; col++) {
85            if (*src & mask) {
86               span.array->x[count] = px + col;
87               span.array->y[count] = py + row;
88               count++;
89            }
90            if (mask == 128U) {
91               src++;
92               mask = 1U;
93            }
94            else {
95               mask = mask << 1;
96            }
97         }
98
99         /* get ready for next row */
100         if (mask != 1)
101            src++;
102      }
103      else {
104         /* Msb first */
105         GLubyte mask = 128U >> (unpack->SkipPixels & 0x7);
106         for (col = 0; col < width; col++) {
107            if (*src & mask) {
108               span.array->x[count] = px + col;
109               span.array->y[count] = py + row;
110               count++;
111            }
112            if (mask == 1U) {
113               src++;
114               mask = 128U;
115            }
116            else {
117               mask = mask >> 1;
118            }
119         }
120
121         /* get ready for next row */
122         if (mask != 128)
123            src++;
124      }
125
126      if (count + width >= SWRAST_MAX_WIDTH || row + 1 == height) {
127         /* flush the span */
128         span.end = count;
129         _swrast_write_rgba_span(ctx, &span);
130         span.end = 0;
131         count = 0;
132      }
133   }
134
135   swrast_render_finish(ctx);
136
137   _mesa_unmap_pbo_source(ctx, unpack);
138}
139
140
141#if 0
142/*
143 * XXX this is another way to implement Bitmap.  Use horizontal runs of
144 * fragments, initializing the mask array to indicate which fragments to
145 * draw or skip.
146 */
147void
148_swrast_Bitmap( struct gl_context *ctx, GLint px, GLint py,
149		GLsizei width, GLsizei height,
150		const struct gl_pixelstore_attrib *unpack,
151		const GLubyte *bitmap )
152{
153   SWcontext *swrast = SWRAST_CONTEXT(ctx);
154   GLint row, col;
155   SWspan span;
156
157   ASSERT(ctx->RenderMode == GL_RENDER);
158   ASSERT(bitmap);
159
160   swrast_render_start(ctx);
161
162   if (SWRAST_CONTEXT(ctx)->NewState)
163      _swrast_validate_derived( ctx );
164
165   INIT_SPAN(span, GL_BITMAP);
166   span.end = width;
167   span.arrayMask = SPAN_MASK;
168   _swrast_span_default_attribs(ctx, &span);
169
170   /*span.arrayMask |= SPAN_MASK;*/  /* we'll init span.mask[] */
171   span.x = px;
172   span.y = py;
173   /*span.end = width;*/
174
175   for (row=0; row<height; row++, span.y++) {
176      const GLubyte *src = (const GLubyte *) _mesa_image_address2d(unpack,
177                 bitmap, width, height, GL_COLOR_INDEX, GL_BITMAP, row, 0);
178
179      if (unpack->LsbFirst) {
180         /* Lsb first */
181         GLubyte mask = 1U << (unpack->SkipPixels & 0x7);
182         for (col=0; col<width; col++) {
183            span.array->mask[col] = (*src & mask) ? GL_TRUE : GL_FALSE;
184            if (mask == 128U) {
185               src++;
186               mask = 1U;
187            }
188            else {
189               mask = mask << 1;
190            }
191         }
192
193         _swrast_write_rgba_span(ctx, &span);
194
195         /* get ready for next row */
196         if (mask != 1)
197            src++;
198      }
199      else {
200         /* Msb first */
201         GLubyte mask = 128U >> (unpack->SkipPixels & 0x7);
202         for (col=0; col<width; col++) {
203            span.array->mask[col] = (*src & mask) ? GL_TRUE : GL_FALSE;
204            if (mask == 1U) {
205               src++;
206               mask = 128U;
207            }
208            else {
209               mask = mask >> 1;
210            }
211         }
212
213         _swrast_write_rgba_span(ctx, &span);
214
215         /* get ready for next row */
216         if (mask != 128)
217            src++;
218      }
219   }
220
221   swrast_render_finish(ctx);
222}
223#endif
224