st_atom_viewport.c revision 6c534b830c6f5427c391c5225c34561141c201ba 
1/**************************************************************************
2 *
3 * Copyright 2007 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
29#include "context.h"
30#include "colormac.h"
31#include "st_context.h"
32#include "st_atom.h"
33#include "pipe/p_context.h"
34#include "cso_cache/cso_context.h"
35
36/**
37 * Update the viewport transformation matrix.  Depends on:
38 *  - viewport pos/size
39 *  - depthrange
40 *  - window pos/size or FBO size
41 */
42static void
43update_viewport( struct st_context *st )
44{
45   GLcontext *ctx = st->ctx;
46   GLfloat yScale, yBias;
47
48   /* _NEW_BUFFERS
49    */
50   if (st_fb_orientation(ctx->DrawBuffer) == Y_0_TOP) {
51      yScale = -1;
52      yBias = (GLfloat)ctx->DrawBuffer->Height;
53   }
54   else {
55      yScale = 1.0;
56      yBias = 0.0;
57   }
58
59   /* _NEW_VIEWPORT
60    */
61   {
62      GLfloat x = (GLfloat)ctx->Viewport.X;
63      GLfloat y = (GLfloat)ctx->Viewport.Y;
64      GLfloat z = ctx->Viewport.Near;
65      GLfloat half_width = (GLfloat)ctx->Viewport.Width / 2.0f;
66      GLfloat half_height = (GLfloat)ctx->Viewport.Height / 2.0f;
67      GLfloat half_depth = (GLfloat)(ctx->Viewport.Far - ctx->Viewport.Near) / 2.0f;
68
69      st->state.viewport.scale[0] = half_width;
70      st->state.viewport.scale[1] = half_height * yScale;
71      st->state.viewport.scale[2] = half_depth;
72      st->state.viewport.scale[3] = 1.0;
73
74      st->state.viewport.translate[0] = half_width + x;
75      st->state.viewport.translate[1] = (half_height + y) * yScale + yBias;
76      st->state.viewport.translate[2] = half_depth + z;
77      st->state.viewport.translate[3] = 0.0;
78
79      cso_set_viewport(st->cso_context, &st->state.viewport);
80   }
81}
82
83
84const struct st_tracked_state st_update_viewport = {
85   "st_update_viewport",				/* name */
86   {							/* dirty */
87      _NEW_BUFFERS | _NEW_VIEWPORT,			/* mesa */
88      0,						/* st */
89   },
90   update_viewport					/* update */
91};
92