1 /**************************************************************************
3 * Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas.
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:
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
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.
26 **************************************************************************/
29 #include "main/context.h"
30 #include "st_context.h"
32 #include "pipe/p_context.h"
33 #include "cso_cache/cso_context.h"
36 * Update the viewport transformation matrix. Depends on:
39 * - window pos/size or FBO size
42 update_viewport( struct st_context
*st
)
44 struct gl_context
*ctx
= st
->ctx
;
45 GLfloat yScale
, yBias
;
49 if (st_fb_orientation(ctx
->DrawBuffer
) == Y_0_TOP
) {
50 /* Drawing to a window. The corresponding gallium surface uses
51 * Y=0=TOP but OpenGL is Y=0=BOTTOM. So we need to invert the viewport.
54 yBias
= (GLfloat
)ctx
->DrawBuffer
->Height
;
57 /* Drawing to an FBO where Y=0=BOTTOM, like OpenGL - don't invert */
65 GLfloat x
= (GLfloat
)ctx
->Viewport
.X
;
66 GLfloat y
= (GLfloat
)ctx
->Viewport
.Y
;
67 GLfloat z
= ctx
->Viewport
.Near
;
68 GLfloat half_width
= (GLfloat
)ctx
->Viewport
.Width
* 0.5f
;
69 GLfloat half_height
= (GLfloat
)ctx
->Viewport
.Height
* 0.5f
;
70 GLfloat half_depth
= (GLfloat
)(ctx
->Viewport
.Far
- ctx
->Viewport
.Near
) * 0.5f
;
72 st
->state
.viewport
.scale
[0] = half_width
;
73 st
->state
.viewport
.scale
[1] = half_height
* yScale
;
74 st
->state
.viewport
.scale
[2] = half_depth
;
75 st
->state
.viewport
.scale
[3] = 1.0;
77 st
->state
.viewport
.translate
[0] = half_width
+ x
;
78 st
->state
.viewport
.translate
[1] = (half_height
+ y
) * yScale
+ yBias
;
79 st
->state
.viewport
.translate
[2] = half_depth
+ z
;
80 st
->state
.viewport
.translate
[3] = 0.0;
82 cso_set_viewport(st
->cso_context
, &st
->state
.viewport
);
87 const struct st_tracked_state st_update_viewport
= {
88 "st_update_viewport", /* name */
90 _NEW_BUFFERS
| _NEW_VIEWPORT
, /* mesa */
93 update_viewport
/* update */