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 
70 static bool
do_blit_readpixels(struct gl_context * ctx,GLint x,GLint y,GLsizei width,GLsizei height,GLenum format,GLenum type,const struct gl_pixelstore_attrib * pack,GLvoid * pixels)71 do_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 
168 void
intelReadPixels(struct gl_context * ctx,GLint x,GLint y,GLsizei width,GLsizei height,GLenum format,GLenum type,const struct gl_pixelstore_attrib * pack,GLvoid * pixels)169 intelReadPixels(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