1 /************************************************************************** 2 * 3 * Copyright 2010 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 "u_format.h" 30 #include "u_sampler.h" 31 32 33 /** 34 * Initialize a pipe_sampler_view. 'view' is considered to have 35 * uninitialized contents. 36 */ 37 static void 38 default_template(struct pipe_sampler_view *view, 39 const struct pipe_resource *texture, 40 enum pipe_format format, 41 unsigned expand_green_blue) 42 { 43 memset(view, 0, sizeof(*view)); 44 45 /* XXX: Check if format is compatible with texture->format. 46 */ 47 48 view->target = texture->target; 49 view->format = format; 50 view->u.tex.first_level = 0; 51 view->u.tex.last_level = texture->last_level; 52 view->u.tex.first_layer = 0; 53 view->u.tex.last_layer = texture->target == PIPE_TEXTURE_3D ? 54 texture->depth0 - 1 : texture->array_size - 1; 55 view->swizzle_r = PIPE_SWIZZLE_X; 56 view->swizzle_g = PIPE_SWIZZLE_Y; 57 view->swizzle_b = PIPE_SWIZZLE_Z; 58 view->swizzle_a = PIPE_SWIZZLE_W; 59 60 /* Override default green and blue component expansion to the requested 61 * one. 62 * 63 * Gallium expands nonexistent components to (0,0,0,1), DX9 expands 64 * to (1,1,1,1). Since alpha is always expanded to 1, and red is 65 * always present, we only really care about green and blue 66 * components. 67 * 68 * To make it look less hackish, one would have to add 69 * PIPE_SWIZZLE_EXPAND to indicate components for expansion 70 * and then override without exceptions or favoring one component 71 * over another. 72 */ 73 if (format != PIPE_FORMAT_A8_UNORM) { 74 const struct util_format_description *desc = util_format_description(format); 75 76 assert(desc); 77 if (desc) { 78 if (desc->swizzle[1] == PIPE_SWIZZLE_0) { 79 view->swizzle_g = expand_green_blue; 80 } 81 if (desc->swizzle[2] == PIPE_SWIZZLE_0) { 82 view->swizzle_b = expand_green_blue; 83 } 84 } 85 } 86 } 87 88 void 89 u_sampler_view_default_template(struct pipe_sampler_view *view, 90 const struct pipe_resource *texture, 91 enum pipe_format format) 92 { 93 /* Expand to (0, 0, 0, 1) */ 94 default_template(view, 95 texture, 96 format, 97 PIPE_SWIZZLE_0); 98 } 99 100 void 101 u_sampler_view_default_dx9_template(struct pipe_sampler_view *view, 102 const struct pipe_resource *texture, 103 enum pipe_format format) 104 { 105 /* Expand to (1, 1, 1, 1) */ 106 default_template(view, 107 texture, 108 format, 109 PIPE_SWIZZLE_1); 110 } 111