1 /**************************************************************************
3 * Copyright 2008 VMware, Inc.
5 * Copyright 2008 VMware, Inc. All rights reserved.
6 * Copyright 2009 Marek Olšák <maraeo@gmail.com>
8 * Permission is hereby granted, free of charge, to any person obtaining a
9 * copy of this software and associated documentation files (the
10 * "Software"), to deal in the Software without restriction, including
11 * without limitation the rights to use, copy, modify, merge, publish,
12 * distribute, sub license, and/or sell copies of the Software, and to
13 * permit persons to whom the Software is furnished to do so, subject to
14 * the following conditions:
16 * The above copyright notice and this permission notice (including the
17 * next paragraph) shall be included in all copies or substantial portions
20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
21 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
22 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
23 * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
24 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
25 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
26 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
28 **************************************************************************/
32 * Texture mapping utility functions.
38 #include "pipe/p_defines.h"
40 #include "util/u_debug.h"
41 #include "util/u_texture.h"
43 void util_map_texcoords2d_onto_cubemap(unsigned face
,
44 const float *in_st
, unsigned in_stride
,
45 float *out_str
, unsigned out_stride
,
51 /* loop over quad verts */
52 for (i
= 0; i
< 4; i
++) {
53 /* Compute sc = +/-scale and tc = +/-scale.
54 * Not +/-1 to avoid cube face selection ambiguity near the edges,
55 * though that can still sometimes happen with this scale factor...
57 * XXX: Yep, there is no safe scale factor that will prevent sampling
58 * the neighbouring face when stretching out. A more reliable solution
59 * would be to clamp (sc, tc) against +/- 1.0-1.0/mipsize, in the shader.
61 * Also, this is not necessary when minifying, or 1:1 blits.
63 const float scale
= allow_scale
? 0.9999f
: 1.0f
;
64 const float sc
= (2 * in_st
[0] - 1) * scale
;
65 const float tc
= (2 * in_st
[1] - 1) * scale
;
68 case PIPE_TEX_FACE_POS_X
:
73 case PIPE_TEX_FACE_NEG_X
:
78 case PIPE_TEX_FACE_POS_Y
:
83 case PIPE_TEX_FACE_NEG_Y
:
88 case PIPE_TEX_FACE_POS_Z
:
93 case PIPE_TEX_FACE_NEG_Z
:
103 out_str
[0] = rx
; /*s*/
104 out_str
[1] = ry
; /*t*/
105 out_str
[2] = rz
; /*r*/
108 out_str
+= out_stride
;