intel_pixel_read.c revision 8004a1cb95b8a195f3f4bbaa8d39d2f3297167de 
1/**************************************************************************
2 *
3 * Copyright 2003 Tungsten Graphics, Inc., Cedar Park, Texas.
4 * All Rights Reserved.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sub license, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
13 *
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
16 * of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
19 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
20 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
21 * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
22 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
23 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
24 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
25 *
26 **************************************************************************/
27
28#include "main/glheader.h"
29#include "main/enums.h"
30#include "main/mtypes.h"
31#include "main/macros.h"
32#include "main/image.h"
33#include "main/bufferobj.h"
34#include "main/state.h"
35#include "swrast/swrast.h"
36
37#include "intel_screen.h"
38#include "intel_context.h"
39#include "intel_blit.h"
40#include "intel_buffers.h"
41#include "intel_regions.h"
42#include "intel_pixel.h"
43#include "intel_buffer_objects.h"
44
45#define FILE_DEBUG_FLAG DEBUG_PIXEL
46
47/* For many applications, the new ability to pull the source buffers
48 * back out of the GTT and then do the packing/conversion operations
49 * in software will be as much of an improvement as trying to get the
50 * blitter and/or texture engine to do the work.
51 *
52 * This step is gated on private backbuffers.
53 *
54 * Obviously the frontbuffer can't be pulled back, so that is either
55 * an argument for blit/texture readpixels, or for blitting to a
56 * temporary and then pulling that back.
57 *
58 * When the destination is a pbo, however, it's not clear if it is
59 * ever going to be pulled to main memory (though the access param
60 * will be a good hint).  So it sounds like we do want to be able to
61 * choose between blit/texture implementation on the gpu and pullback
62 * and cpu-based copying.
63 *
64 * Unless you can magically turn client memory into a PBO for the
65 * duration of this call, there will be a cpu-based copying step in
66 * any case.
67 */
68
69static GLboolean
70do_blit_readpixels(struct gl_context * ctx,
71                   GLint x, GLint y, GLsizei width, GLsizei height,
72                   GLenum format, GLenum type,
73                   const struct gl_pixelstore_attrib *pack, GLvoid * pixels)
74{
75   struct intel_context *intel = intel_context(ctx);
76   struct intel_region *src = intel_readbuf_region(intel);
77   struct intel_buffer_object *dst = intel_buffer_object(pack->BufferObj);
78   GLuint dst_offset;
79   GLuint rowLength;
80   drm_intel_bo *dst_buffer;
81   GLboolean all;
82   GLint dst_x, dst_y;
83   GLuint dirty;
84
85   DBG("%s\n", __FUNCTION__);
86
87   if (!src)
88      return GL_FALSE;
89
90   if (!_mesa_is_bufferobj(pack->BufferObj)) {
91      /* PBO only for now:
92       */
93      DBG("%s - not PBO\n", __FUNCTION__);
94      return GL_FALSE;
95   }
96
97
98   if (ctx->_ImageTransferState ||
99       !intel_check_blit_format(src, format, type)) {
100      DBG("%s - bad format for blit\n", __FUNCTION__);
101      return GL_FALSE;
102   }
103
104   if (pack->Alignment != 1 || pack->SwapBytes || pack->LsbFirst) {
105      DBG("%s: bad packing params\n", __FUNCTION__);
106      return GL_FALSE;
107   }
108
109   if (pack->RowLength > 0)
110      rowLength = pack->RowLength;
111   else
112      rowLength = width;
113
114   if (pack->Invert) {
115      DBG("%s: MESA_PACK_INVERT not done yet\n", __FUNCTION__);
116      return GL_FALSE;
117   }
118   else {
119      if (ctx->ReadBuffer->Name == 0)
120	 rowLength = -rowLength;
121   }
122
123   dst_offset = (GLintptr) _mesa_image_address(2, pack, pixels, width, height,
124					       format, type, 0, 0, 0);
125
126   if (!_mesa_clip_copytexsubimage(ctx,
127				   &dst_x, &dst_y,
128				   &x, &y,
129				   &width, &height)) {
130      return GL_TRUE;
131   }
132
133   dirty = intel->front_buffer_dirty;
134   intel_prepare_render(intel);
135   intel->front_buffer_dirty = dirty;
136
137   all = (width * height * src->cpp == dst->Base.Size &&
138	  x == 0 && dst_offset == 0);
139
140   dst_x = 0;
141   dst_y = 0;
142
143   dst_buffer = intel_bufferobj_buffer(intel, dst,
144				       all ? INTEL_WRITE_FULL :
145				       INTEL_WRITE_PART);
146
147   if (ctx->ReadBuffer->Name == 0)
148      y = ctx->ReadBuffer->Height - (y + height);
149
150   if (!intelEmitCopyBlit(intel,
151			  src->cpp,
152			  src->pitch, src->bo, 0, src->tiling,
153			  rowLength, dst_buffer, dst_offset, GL_FALSE,
154			  x, y,
155			  dst_x, dst_y,
156			  width, height,
157			  GL_COPY)) {
158      return GL_FALSE;
159   }
160
161   DBG("%s - DONE\n", __FUNCTION__);
162
163   return GL_TRUE;
164}
165
166void
167intelReadPixels(struct gl_context * ctx,
168                GLint x, GLint y, GLsizei width, GLsizei height,
169                GLenum format, GLenum type,
170                const struct gl_pixelstore_attrib *pack, GLvoid * pixels)
171{
172   struct intel_context *intel = intel_context(ctx);
173   GLboolean dirty;
174
175   DBG("%s\n", __FUNCTION__);
176
177   if (do_blit_readpixels
178       (ctx, x, y, width, height, format, type, pack, pixels))
179      return;
180
181   intel_flush(ctx);
182
183   /* glReadPixels() wont dirty the front buffer, so reset the dirty
184    * flag after calling intel_prepare_render(). */
185   dirty = intel->front_buffer_dirty;
186   intel_prepare_render(intel);
187   intel->front_buffer_dirty = dirty;
188
189   fallback_debug("%s: fallback to swrast\n", __FUNCTION__);
190
191   /* Update Mesa state before calling down into _swrast_ReadPixels, as
192    * the spans code requires the computed buffer states to be up to date,
193    * but _swrast_ReadPixels only updates Mesa state after setting up
194    * the spans code.
195    */
196
197   if (ctx->NewState)
198      _mesa_update_state(ctx);
199
200   _swrast_ReadPixels(ctx, x, y, width, height, format, type, pack, pixels);
201
202   /* There's an intel_prepare_render() call in intelSpanRenderStart(). */
203   intel->front_buffer_dirty = dirty;
204}
205