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/fbobject.h"
33#include "main/image.h"
34#include "main/bufferobj.h"
35#include "main/readpix.h"
36#include "main/state.h"
37
38#include "intel_screen.h"
39#include "intel_context.h"
40#include "intel_blit.h"
41#include "intel_buffers.h"
42#include "intel_regions.h"
43#include "intel_pixel.h"
44#include "intel_buffer_objects.h"
45
46#define FILE_DEBUG_FLAG DEBUG_PIXEL
47
48/* For many applications, the new ability to pull the source buffers
49 * back out of the GTT and then do the packing/conversion operations
50 * in software will be as much of an improvement as trying to get the
51 * blitter and/or texture engine to do the work.
52 *
53 * This step is gated on private backbuffers.
54 *
55 * Obviously the frontbuffer can't be pulled back, so that is either
56 * an argument for blit/texture readpixels, or for blitting to a
57 * temporary and then pulling that back.
58 *
59 * When the destination is a pbo, however, it's not clear if it is
60 * ever going to be pulled to main memory (though the access param
61 * will be a good hint).  So it sounds like we do want to be able to
62 * choose between blit/texture implementation on the gpu and pullback
63 * and cpu-based copying.
64 *
65 * Unless you can magically turn client memory into a PBO for the
66 * duration of this call, there will be a cpu-based copying step in
67 * any case.
68 */
69
70static bool
71do_blit_readpixels(struct gl_context * ctx,
72                   GLint x, GLint y, GLsizei width, GLsizei height,
73                   GLenum format, GLenum type,
74                   const struct gl_pixelstore_attrib *pack, GLvoid * pixels)
75{
76   struct intel_context *intel = intel_context(ctx);
77   struct intel_region *src = intel_readbuf_region(intel);
78   struct intel_buffer_object *dst = intel_buffer_object(pack->BufferObj);
79   GLuint dst_offset;
80   GLuint rowLength;
81   drm_intel_bo *dst_buffer;
82   bool all;
83   GLint dst_x, dst_y;
84   GLuint dirty;
85
86   DBG("%s\n", __FUNCTION__);
87
88   if (!src)
89      return false;
90
91   if (!_mesa_is_bufferobj(pack->BufferObj)) {
92      /* PBO only for now:
93       */
94      DBG("%s - not PBO\n", __FUNCTION__);
95      return false;
96   }
97
98
99   if (ctx->_ImageTransferState ||
100       !intel_check_blit_format(src, format, type)) {
101      DBG("%s - bad format for blit\n", __FUNCTION__);
102      return false;
103   }
104
105   if (pack->Alignment != 1 || pack->SwapBytes || pack->LsbFirst) {
106      DBG("%s: bad packing params\n", __FUNCTION__);
107      return false;
108   }
109
110   if (pack->RowLength > 0)
111      rowLength = pack->RowLength;
112   else
113      rowLength = width;
114
115   if (pack->Invert) {
116      DBG("%s: MESA_PACK_INVERT not done yet\n", __FUNCTION__);
117      return false;
118   }
119   else {
120      if (_mesa_is_winsys_fbo(ctx->ReadBuffer))
121	 rowLength = -rowLength;
122   }
123
124   dst_offset = (GLintptr)pixels;
125   dst_offset += _mesa_image_offset(2, pack, width, height,
126				    format, type, 0, 0, 0);
127
128   if (!_mesa_clip_copytexsubimage(ctx,
129				   &dst_x, &dst_y,
130				   &x, &y,
131				   &width, &height)) {
132      return true;
133   }
134
135   dirty = intel->front_buffer_dirty;
136   intel_prepare_render(intel);
137   intel->front_buffer_dirty = dirty;
138
139   all = (width * height * src->cpp == dst->Base.Size &&
140	  x == 0 && dst_offset == 0);
141
142   dst_x = 0;
143   dst_y = 0;
144
145   dst_buffer = intel_bufferobj_buffer(intel, dst,
146				       all ? INTEL_WRITE_FULL :
147				       INTEL_WRITE_PART);
148
149   if (_mesa_is_winsys_fbo(ctx->ReadBuffer))
150      y = ctx->ReadBuffer->Height - (y + height);
151
152   if (!intelEmitCopyBlit(intel,
153			  src->cpp,
154			  src->pitch, src->bo, 0, src->tiling,
155			  rowLength, dst_buffer, dst_offset, false,
156			  x, y,
157			  dst_x, dst_y,
158			  width, height,
159			  GL_COPY)) {
160      return false;
161   }
162
163   DBG("%s - DONE\n", __FUNCTION__);
164
165   return true;
166}
167
168void
169intelReadPixels(struct gl_context * ctx,
170                GLint x, GLint y, GLsizei width, GLsizei height,
171                GLenum format, GLenum type,
172                const struct gl_pixelstore_attrib *pack, GLvoid * pixels)
173{
174   struct intel_context *intel = intel_context(ctx);
175   bool dirty;
176
177   intel_flush_rendering_to_batch(ctx);
178
179   DBG("%s\n", __FUNCTION__);
180
181   if (do_blit_readpixels
182       (ctx, x, y, width, height, format, type, pack, pixels))
183      return;
184
185   /* glReadPixels() wont dirty the front buffer, so reset the dirty
186    * flag after calling intel_prepare_render(). */
187   dirty = intel->front_buffer_dirty;
188   intel_prepare_render(intel);
189   intel->front_buffer_dirty = dirty;
190
191   fallback_debug("%s: fallback to swrast\n", __FUNCTION__);
192
193   /* Update Mesa state before calling _mesa_readpixels().
194    * XXX this may not be needed since ReadPixels no longer uses the
195    * span code.
196    */
197
198   if (ctx->NewState)
199      _mesa_update_state(ctx);
200
201   _mesa_readpixels(ctx, x, y, width, height, format, type, pack, pixels);
202
203   /* There's an intel_prepare_render() call in intelSpanRenderStart(). */
204   intel->front_buffer_dirty = dirty;
205}
206