summaryrefslogtreecommitdiff
path: root/src/mesa/swrast/s_clear.c
blob: c26b4be0d9e432a1cf9992b9a48e64682abf55ba (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
/*
 * Mesa 3-D graphics library
 *
 * Copyright (C) 1999-2008  Brian Paul   All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 */

#include "main/glheader.h"
#include "main/accum.h"
#include "main/condrender.h"
#include "main/format_pack.h"
#include "main/macros.h"
#include "main/imports.h"
#include "main/mtypes.h"

#include "s_context.h"
#include "s_depth.h"
#include "s_stencil.h"



/**
 * Clear an rgba color buffer with masking if needed.
 */
static void
clear_rgba_buffer(struct gl_context *ctx, struct gl_renderbuffer *rb,
                  const GLubyte colorMask[4])
{
   const GLint x = ctx->DrawBuffer->_Xmin;
   const GLint y = ctx->DrawBuffer->_Ymin;
   const GLint height = ctx->DrawBuffer->_Ymax - ctx->DrawBuffer->_Ymin;
   const GLint width  = ctx->DrawBuffer->_Xmax - ctx->DrawBuffer->_Xmin;
   const GLuint pixelSize = _mesa_get_format_bytes(rb->Format);
   const GLboolean doMasking = (colorMask[0] == 0 ||
                                colorMask[1] == 0 ||
                                colorMask[2] == 0 ||
                                colorMask[3] == 0);
   const GLfloat (*clearColor)[4] =
      (const GLfloat (*)[4]) ctx->Color.ClearColor.f;
   GLbitfield mapMode = GL_MAP_WRITE_BIT;
   GLubyte *map;
   GLint rowStride;
   GLint i, j;

   if (doMasking) {
      /* we'll need to read buffer values too */
      mapMode |= GL_MAP_READ_BIT;
   }

   /* map dest buffer */
   ctx->Driver.MapRenderbuffer(ctx, rb, x, y, width, height,
                               mapMode, &map, &rowStride);
   if (!map) {
      _mesa_error(ctx, GL_OUT_OF_MEMORY, "glClear(color)");
      return;
   }

   /* for 1, 2, 4-byte clearing */
#define SIMPLE_TYPE_CLEAR(TYPE)                                         \
   do {                                                                 \
      TYPE pixel, pixelMask;                                            \
      _mesa_pack_float_rgba_row(rb->Format, 1, clearColor, &pixel);     \
      if (doMasking) {                                                  \
         _mesa_pack_colormask(rb->Format, colorMask, &pixelMask);       \
         pixel &= pixelMask;                                            \
         pixelMask = ~pixelMask;                                        \
      }                                                                 \
      for (i = 0; i < height; i++) {                                    \
         TYPE *row = (TYPE *) map;                                      \
         if (doMasking) {                                               \
            for (j = 0; j < width; j++) {                               \
               row[j] = (row[j] & pixelMask) | pixel;                   \
            }                                                           \
         }                                                              \
         else {                                                         \
            for (j = 0; j < width; j++) {                               \
               row[j] = pixel;                                          \
            }                                                           \
         }                                                              \
         map += rowStride;                                              \
      }                                                                 \
   } while (0)


   /* for 3, 6, 8, 12, 16-byte clearing */
#define MULTI_WORD_CLEAR(TYPE, N)                                       \
   do {                                                                 \
      TYPE pixel[N], pixelMask[N];                                      \
      GLuint k;                                                         \
      _mesa_pack_float_rgba_row(rb->Format, 1, clearColor, pixel);      \
      if (doMasking) {                                                  \
         _mesa_pack_colormask(rb->Format, colorMask, pixelMask);        \
         for (k = 0; k < N; k++) {                                      \
            pixel[k] &= pixelMask[k];                                   \
            pixelMask[k] = ~pixelMask[k];                               \
         }                                                              \
      }                                                                 \
      for (i = 0; i < height; i++) {                                    \
         TYPE *row = (TYPE *) map;                                      \
         if (doMasking) {                                               \
            for (j = 0; j < width; j++) {                               \
               for (k = 0; k < N; k++) {                                \
                  row[j * N + k] =                                      \
                     (row[j * N + k] & pixelMask[k]) | pixel[k];        \
               }                                                        \
            }                                                           \
         }                                                              \
         else {                                                         \
            for (j = 0; j < width; j++) {                               \
               for (k = 0; k < N; k++) {                                \
                  row[j * N + k] = pixel[k];                            \
               }                                                        \
            }                                                           \
         }                                                              \
         map += rowStride;                                              \
      }                                                                 \
   } while(0)

   switch (pixelSize) {
   case 1:
      SIMPLE_TYPE_CLEAR(GLubyte);
      break;
   case 2:
      SIMPLE_TYPE_CLEAR(GLushort);
      break;
   case 3:
      MULTI_WORD_CLEAR(GLubyte, 3);
      break;
   case 4:
      SIMPLE_TYPE_CLEAR(GLuint);
      break;
   case 6:
      MULTI_WORD_CLEAR(GLushort, 3);
      break;
   case 8:
      MULTI_WORD_CLEAR(GLuint, 2);
      break;
   case 12:
      MULTI_WORD_CLEAR(GLuint, 3);
      break;
   case 16:
      MULTI_WORD_CLEAR(GLuint, 4);
      break;
   default:
      _mesa_problem(ctx, "bad pixel size in clear_rgba_buffer()");
   }

   /* unmap buffer */
   ctx->Driver.UnmapRenderbuffer(ctx, rb);
}


/**
 * Clear the front/back/left/right/aux color buffers.
 * This function is usually only called if the device driver can't
 * clear its own color buffers for some reason (such as with masking).
 */
static void
clear_color_buffers(struct gl_context *ctx)
{
   GLuint buf;

   for (buf = 0; buf < ctx->DrawBuffer->_NumColorDrawBuffers; buf++) {
      struct gl_renderbuffer *rb = ctx->DrawBuffer->_ColorDrawBuffers[buf];

      /* If this is an ES2 context or GL_ARB_ES2_compatibility is supported,
       * the framebuffer can be complete with some attachments be missing.  In
       * this case the _ColorDrawBuffers pointer will be NULL.
       */
      if (rb == NULL)
	 continue;

      clear_rgba_buffer(ctx, rb, ctx->Color.ColorMask[buf]);
   }
}


/**
 * Called via the device driver's ctx->Driver.Clear() function if the
 * device driver can't clear one or more of the buffers itself.
 * \param buffers  bitfield of BUFFER_BIT_* values indicating which
 *                 renderbuffers are to be cleared.
 * \param all  if GL_TRUE, clear whole buffer, else clear specified region.
 */
void
_swrast_Clear(struct gl_context *ctx, GLbitfield buffers)
{
   const GLbitfield BUFFER_DS = BUFFER_BIT_DEPTH | BUFFER_BIT_STENCIL;

#ifdef DEBUG_FOO
   {
      const GLbitfield legalBits =
         BUFFER_BIT_FRONT_LEFT |
	 BUFFER_BIT_FRONT_RIGHT |
	 BUFFER_BIT_BACK_LEFT |
	 BUFFER_BIT_BACK_RIGHT |
	 BUFFER_BIT_DEPTH |
	 BUFFER_BIT_STENCIL |
	 BUFFER_BIT_ACCUM |
         BUFFER_BIT_AUX0;
      assert((buffers & (~legalBits)) == 0);
   }
#endif

   if (!_mesa_check_conditional_render(ctx))
      return; /* don't clear */

   if (SWRAST_CONTEXT(ctx)->NewState)
      _swrast_validate_derived(ctx);

   if ((buffers & BUFFER_BITS_COLOR)
       && (ctx->DrawBuffer->_NumColorDrawBuffers > 0)) {
      clear_color_buffers(ctx);
   }

   if (buffers & BUFFER_BIT_ACCUM) {
      _mesa_clear_accum_buffer(ctx);
   }

   if (buffers & BUFFER_DS) {
      struct gl_renderbuffer *depthRb =
         ctx->DrawBuffer->Attachment[BUFFER_DEPTH].Renderbuffer;
      struct gl_renderbuffer *stencilRb =
         ctx->DrawBuffer->Attachment[BUFFER_STENCIL].Renderbuffer;

      if ((buffers & BUFFER_DS) == BUFFER_DS && depthRb == stencilRb) {
         /* clear depth and stencil together */
         _swrast_clear_depth_stencil_buffer(ctx);
      }
      else {
         /* clear depth, stencil separately */
         if (buffers & BUFFER_BIT_DEPTH) {
            _swrast_clear_depth_buffer(ctx);
         }
         if (buffers & BUFFER_BIT_STENCIL) {
            _swrast_clear_stencil_buffer(ctx);
         }
      }
   }
}