1 /**************************************************************************
2 *
3 * Copyright 2007 VMware, Inc.
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 VMWARE 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 "main/context.h"
30 #include "main/viewport.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 */
42 static void
update_viewport(struct st_context * st)43 update_viewport( struct st_context *st )
44 {
45 struct gl_context *ctx = st->ctx;
46 GLfloat yScale, yBias;
47 unsigned i;
48 /* _NEW_BUFFERS
49 */
50 if (st_fb_orientation(ctx->DrawBuffer) == Y_0_TOP) {
51 /* Drawing to a window. The corresponding gallium surface uses
52 * Y=0=TOP but OpenGL is Y=0=BOTTOM. So we need to invert the viewport.
53 */
54 yScale = -1;
55 yBias = (GLfloat)ctx->DrawBuffer->Height;
56 }
57 else {
58 /* Drawing to an FBO where Y=0=BOTTOM, like OpenGL - don't invert */
59 yScale = 1.0;
60 yBias = 0.0;
61 }
62
63 /* _NEW_VIEWPORT
64 */
65 for (i = 0; i < ctx->Const.MaxViewports; i++)
66 {
67 float scale[3], translate[3];
68 _mesa_get_viewport_xform(ctx, i, scale, translate);
69
70 st->state.viewport[i].scale[0] = scale[0];
71 st->state.viewport[i].scale[1] = scale[1] * yScale;
72 st->state.viewport[i].scale[2] = scale[2];
73
74 st->state.viewport[i].translate[0] = translate[0];
75 st->state.viewport[i].translate[1] = translate[1] * yScale + yBias;
76 st->state.viewport[i].translate[2] = translate[2];
77 }
78
79 cso_set_viewport(st->cso_context, &st->state.viewport[0]);
80 if (ctx->Const.MaxViewports > 1)
81 st->pipe->set_viewport_states(st->pipe, 1, ctx->Const.MaxViewports - 1, &st->state.viewport[1]);
82 }
83
84
85 const struct st_tracked_state st_update_viewport = {
86 update_viewport /* update */
87 };
88