1/************************************************************************** 2 * 3 * Copyright 2002 VMware, Inc. 4 * Copyright 2011 Dave Airlie (ARB_vertex_type_2_10_10_10_rev support) 5 * Copyright 2020 Advanced Micro Devices, Inc. 6 * All Rights Reserved. 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 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. 27 * 28 **************************************************************************/ 29 30#ifndef VBO_UTIL_H 31#define VBO_UTIL_H 32 33static inline float conv_ui10_to_norm_float(unsigned ui10) 34{ 35 return ui10 / 1023.0f; 36} 37 38static inline float conv_ui2_to_norm_float(unsigned ui2) 39{ 40 return ui2 / 3.0f; 41} 42 43struct attr_bits_10 {signed int x:10;}; 44struct attr_bits_2 {signed int x:2;}; 45 46static inline float conv_i10_to_i(int i10) 47{ 48 struct attr_bits_10 val; 49 val.x = i10; 50 return (float)val.x; 51} 52 53static inline float conv_i2_to_i(int i2) 54{ 55 struct attr_bits_2 val; 56 val.x = i2; 57 return (float)val.x; 58} 59 60static inline float conv_i10_to_norm_float(const struct gl_context *ctx, int i10) 61{ 62 struct attr_bits_10 val; 63 val.x = i10; 64 65 /* Traditionally, OpenGL has had two equations for converting from 66 * normalized fixed-point data to floating-point data. In the OpenGL 3.2 67 * specification, these are equations 2.2 and 2.3, respectively: 68 * 69 * f = (2c + 1)/(2^b - 1). (2.2) 70 * 71 * Comments below this equation state: "In general, this representation is 72 * used for signed normalized fixed-point parameters in GL commands, such 73 * as vertex attribute values." Which is what we're doing here. 74 * 75 * f = max{c/(2^(b-1) - 1), -1.0} (2.3) 76 * 77 * Comments below this equation state: "In general, this representation is 78 * used for signed normalized fixed-point texture or floating point values." 79 * 80 * OpenGL 4.2+ and ES 3.0 remedy this and state that equation 2.3 (above) 81 * is used in every case. They remove equation 2.2 completely. 82 */ 83 if (_mesa_is_gles3(ctx) || 84 (_mesa_is_desktop_gl(ctx) && ctx->Version >= 42)) { 85 /* Equation 2.3 above. */ 86 float f = ((float) val.x) / 511.0F; 87 return MAX2(f, -1.0f); 88 } else { 89 /* Equation 2.2 above. */ 90 return (2.0F * (float)val.x + 1.0F) * (1.0F / 1023.0F); 91 } 92} 93 94static inline float conv_i2_to_norm_float(const struct gl_context *ctx, int i2) 95{ 96 struct attr_bits_2 val; 97 val.x = i2; 98 99 if (_mesa_is_gles3(ctx) || 100 (_mesa_is_desktop_gl(ctx) && ctx->Version >= 42)) { 101 /* Equation 2.3 above. */ 102 float f = (float) val.x; 103 return MAX2(f, -1.0f); 104 } else { 105 /* Equation 2.2 above. */ 106 return (2.0F * (float)val.x + 1.0F) * (1.0F / 3.0F); 107 } 108} 109 110#define ERROR_IF_NOT_PACKED_TYPE(ctx, type, func) \ 111 if (type != GL_INT_2_10_10_10_REV && type != GL_UNSIGNED_INT_2_10_10_10_REV) { \ 112 _mesa_error(ctx, GL_INVALID_ENUM, "%s(type)", func); \ 113 return; \ 114 } 115 116/* Extended version of ERROR_IF_NOT_PACKED_TYPE which also 117 * accepts GL_UNSIGNED_INT_10F_11F_11F_REV. 118 * 119 * Only used for VertexAttribP[123]ui[v]; VertexAttribP4* cannot use this type, 120 * and neither can legacy vertex attribs. 121 */ 122#define ERROR_IF_NOT_PACKED_TYPE_EXT(ctx, type, func) \ 123 if (type != GL_INT_2_10_10_10_REV && type != GL_UNSIGNED_INT_2_10_10_10_REV && \ 124 type != GL_UNSIGNED_INT_10F_11F_11F_REV) { \ 125 _mesa_error(ctx, GL_INVALID_ENUM, "%s(type)", func); \ 126 return; \ 127 } 128 129#endif 130