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Diffstat (limited to 'src/gallium/auxiliary/util/u_texture.c')
-rw-r--r-- | src/gallium/auxiliary/util/u_texture.c | 102 |
1 files changed, 102 insertions, 0 deletions
diff --git a/src/gallium/auxiliary/util/u_texture.c b/src/gallium/auxiliary/util/u_texture.c new file mode 100644 index 0000000000..cd477ab640 --- /dev/null +++ b/src/gallium/auxiliary/util/u_texture.c @@ -0,0 +1,102 @@ +/************************************************************************** + * + * Copyright 2008 Tungsten Graphics, Inc., Cedar Park, Texas. + * All Rights Reserved. + * Copyright 2008 VMware, Inc. All rights reserved. + * Copyright 2009 Marek Olšák <maraeo@gmail.com> + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the + * "Software"), to deal in the Software without restriction, including + * without limitation the rights to use, copy, modify, merge, publish, + * distribute, sub license, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * The above copyright notice and this permission notice (including the + * next paragraph) shall be included in all copies or substantial portions + * of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. + * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR + * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, + * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE + * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + * + **************************************************************************/ + +/** + * @file + * Texture mapping utility functions. + * + * @author Brian Paul + * Marek Olšák + */ + +#include "pipe/p_defines.h" + +#include "util/u_texture.h" + +void util_map_texcoords2d_onto_cubemap(unsigned face, + const float *in_st, unsigned in_stride, + float *out_str, unsigned out_stride) +{ + int i; + float rx, ry, rz; + + /* loop over quad verts */ + for (i = 0; i < 4; i++) { + /* Compute sc = +/-scale and tc = +/-scale. + * Not +/-1 to avoid cube face selection ambiguity near the edges, + * though that can still sometimes happen with this scale factor... + */ + const float scale = 0.9999f; + const float sc = (2 * in_st[0] - 1) * scale; + const float tc = (2 * in_st[1] - 1) * scale; + + switch (face) { + case PIPE_TEX_FACE_POS_X: + rx = 1; + ry = -tc; + rz = -sc; + break; + case PIPE_TEX_FACE_NEG_X: + rx = -1; + ry = -tc; + rz = sc; + break; + case PIPE_TEX_FACE_POS_Y: + rx = sc; + ry = 1; + rz = tc; + break; + case PIPE_TEX_FACE_NEG_Y: + rx = sc; + ry = -1; + rz = -tc; + break; + case PIPE_TEX_FACE_POS_Z: + rx = sc; + ry = -tc; + rz = 1; + break; + case PIPE_TEX_FACE_NEG_Z: + rx = -sc; + ry = -tc; + rz = -1; + break; + default: + rx = ry = rz = 0; + assert(0); + } + + out_str[0] = rx; /*s*/ + out_str[1] = ry; /*t*/ + out_str[2] = rz; /*r*/ + + in_st += in_stride; + out_str += out_stride; + } +} |