1 /************************************************************************** 2 * 3 * Copyright 2008 Tungsten Graphics, Inc., Cedar Park, Texas. 4 * All Rights Reserved. 5 * Copyright 2008 VMware, Inc. All rights reserved. 6 * Copyright 2009 Marek Olk <maraeo (at) gmail.com> 7 * 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: 15 * 16 * The above copyright notice and this permission notice (including the 17 * next paragraph) shall be included in all copies or substantial portions 18 * of the Software. 19 * 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 TUNGSTEN GRAPHICS 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. 27 * 28 **************************************************************************/ 29 30 /** 31 * @file 32 * Texture mapping utility functions. 33 * 34 * @author Brian Paul 35 * Marek Olk 36 */ 37 38 #include "pipe/p_defines.h" 39 40 #include "util/u_debug.h" 41 #include "util/u_texture.h" 42 43 void util_map_texcoords2d_onto_cubemap(unsigned face, 44 const float *in_st, unsigned in_stride, 45 float *out_str, unsigned out_stride) 46 { 47 int i; 48 float rx, ry, rz; 49 50 /* loop over quad verts */ 51 for (i = 0; i < 4; i++) { 52 /* Compute sc = +/-scale and tc = +/-scale. 53 * Not +/-1 to avoid cube face selection ambiguity near the edges, 54 * though that can still sometimes happen with this scale factor... 55 */ 56 const float scale = 0.9999f; 57 const float sc = (2 * in_st[0] - 1) * scale; 58 const float tc = (2 * in_st[1] - 1) * scale; 59 60 switch (face) { 61 case PIPE_TEX_FACE_POS_X: 62 rx = 1; 63 ry = -tc; 64 rz = -sc; 65 break; 66 case PIPE_TEX_FACE_NEG_X: 67 rx = -1; 68 ry = -tc; 69 rz = sc; 70 break; 71 case PIPE_TEX_FACE_POS_Y: 72 rx = sc; 73 ry = 1; 74 rz = tc; 75 break; 76 case PIPE_TEX_FACE_NEG_Y: 77 rx = sc; 78 ry = -1; 79 rz = -tc; 80 break; 81 case PIPE_TEX_FACE_POS_Z: 82 rx = sc; 83 ry = -tc; 84 rz = 1; 85 break; 86 case PIPE_TEX_FACE_NEG_Z: 87 rx = -sc; 88 ry = -tc; 89 rz = -1; 90 break; 91 default: 92 rx = ry = rz = 0; 93 assert(0); 94 } 95 96 out_str[0] = rx; /*s*/ 97 out_str[1] = ry; /*t*/ 98 out_str[2] = rz; /*r*/ 99 100 in_st += in_stride; 101 out_str += out_stride; 102 } 103 } 104
