1 /* 2 * Copyright (C) 2011 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 /** @file rs_math.rsh 18 * \brief todo-jsams 19 * 20 * todo-jsams 21 * 22 */ 23 24 #ifndef __RS_MATH_RSH__ 25 #define __RS_MATH_RSH__ 26 27 28 /** 29 * Return a random value between 0 (or min_value) and max_malue. 30 */ 31 extern int __attribute__((overloadable)) 32 rsRand(int max_value); 33 /** 34 * \overload 35 */ 36 extern int __attribute__((overloadable)) 37 rsRand(int min_value, int max_value); 38 /** 39 * \overload 40 */ 41 extern float __attribute__((overloadable)) 42 rsRand(float max_value); 43 /** 44 * \overload 45 */ 46 extern float __attribute__((overloadable)) 47 rsRand(float min_value, float max_value); 48 49 /** 50 * Returns the fractional part of a float 51 */ 52 extern float __attribute__((const, overloadable)) 53 rsFrac(float); 54 55 56 ///////////////////////////////////////////////////// 57 // int ops 58 ///////////////////////////////////////////////////// 59 60 /** 61 * Clamp the value amount between low and high. 62 * 63 * @param amount The value to clamp 64 * @param low 65 * @param high 66 */ 67 _RS_RUNTIME uint __attribute__((const, overloadable, always_inline)) rsClamp(uint amount, uint low, uint high); 68 69 /** 70 * \overload 71 */ 72 _RS_RUNTIME int __attribute__((const, overloadable, always_inline)) rsClamp(int amount, int low, int high); 73 /** 74 * \overload 75 */ 76 _RS_RUNTIME ushort __attribute__((const, overloadable, always_inline)) rsClamp(ushort amount, ushort low, ushort high); 77 /** 78 * \overload 79 */ 80 _RS_RUNTIME short __attribute__((const, overloadable, always_inline)) rsClamp(short amount, short low, short high); 81 /** 82 * \overload 83 */ 84 _RS_RUNTIME uchar __attribute__((const, overloadable, always_inline)) rsClamp(uchar amount, uchar low, uchar high); 85 /** 86 * \overload 87 */ 88 _RS_RUNTIME char __attribute__((const, overloadable, always_inline)) rsClamp(char amount, char low, char high); 89 90 91 /** 92 * Computes 6 frustum planes from the view projection matrix 93 * @param viewProj matrix to extract planes from 94 * @param left plane 95 * @param right plane 96 * @param top plane 97 * @param bottom plane 98 * @param near plane 99 * @param far plane 100 */ 101 __inline__ static void __attribute__((overloadable, always_inline)) 102 rsExtractFrustumPlanes(const rs_matrix4x4 *viewProj, 103 float4 *left, float4 *right, 104 float4 *top, float4 *bottom, 105 float4 *near, float4 *far) { 106 // x y z w = a b c d in the plane equation 107 left->x = viewProj->m[3] + viewProj->m[0]; 108 left->y = viewProj->m[7] + viewProj->m[4]; 109 left->z = viewProj->m[11] + viewProj->m[8]; 110 left->w = viewProj->m[15] + viewProj->m[12]; 111 112 right->x = viewProj->m[3] - viewProj->m[0]; 113 right->y = viewProj->m[7] - viewProj->m[4]; 114 right->z = viewProj->m[11] - viewProj->m[8]; 115 right->w = viewProj->m[15] - viewProj->m[12]; 116 117 top->x = viewProj->m[3] - viewProj->m[1]; 118 top->y = viewProj->m[7] - viewProj->m[5]; 119 top->z = viewProj->m[11] - viewProj->m[9]; 120 top->w = viewProj->m[15] - viewProj->m[13]; 121 122 bottom->x = viewProj->m[3] + viewProj->m[1]; 123 bottom->y = viewProj->m[7] + viewProj->m[5]; 124 bottom->z = viewProj->m[11] + viewProj->m[9]; 125 bottom->w = viewProj->m[15] + viewProj->m[13]; 126 127 near->x = viewProj->m[3] + viewProj->m[2]; 128 near->y = viewProj->m[7] + viewProj->m[6]; 129 near->z = viewProj->m[11] + viewProj->m[10]; 130 near->w = viewProj->m[15] + viewProj->m[14]; 131 132 far->x = viewProj->m[3] - viewProj->m[2]; 133 far->y = viewProj->m[7] - viewProj->m[6]; 134 far->z = viewProj->m[11] - viewProj->m[10]; 135 far->w = viewProj->m[15] - viewProj->m[14]; 136 137 float len = length(left->xyz); 138 *left /= len; 139 len = length(right->xyz); 140 *right /= len; 141 len = length(top->xyz); 142 *top /= len; 143 len = length(bottom->xyz); 144 *bottom /= len; 145 len = length(near->xyz); 146 *near /= len; 147 len = length(far->xyz); 148 *far /= len; 149 } 150 151 /** 152 * Checks if a sphere is withing the 6 frustum planes 153 * @param sphere float4 representing the sphere 154 * @param left plane 155 * @param right plane 156 * @param top plane 157 * @param bottom plane 158 * @param near plane 159 * @param far plane 160 */ 161 __inline__ static bool __attribute__((overloadable, always_inline)) 162 rsIsSphereInFrustum(float4 *sphere, 163 float4 *left, float4 *right, 164 float4 *top, float4 *bottom, 165 float4 *near, float4 *far) { 166 167 float distToCenter = dot(left->xyz, sphere->xyz) + left->w; 168 if (distToCenter < -sphere->w) { 169 return false; 170 } 171 distToCenter = dot(right->xyz, sphere->xyz) + right->w; 172 if (distToCenter < -sphere->w) { 173 return false; 174 } 175 distToCenter = dot(top->xyz, sphere->xyz) + top->w; 176 if (distToCenter < -sphere->w) { 177 return false; 178 } 179 distToCenter = dot(bottom->xyz, sphere->xyz) + bottom->w; 180 if (distToCenter < -sphere->w) { 181 return false; 182 } 183 distToCenter = dot(near->xyz, sphere->xyz) + near->w; 184 if (distToCenter < -sphere->w) { 185 return false; 186 } 187 distToCenter = dot(far->xyz, sphere->xyz) + far->w; 188 if (distToCenter < -sphere->w) { 189 return false; 190 } 191 return true; 192 } 193 194 195 /** 196 * Pack floating point (0-1) RGB values into a uchar4. The alpha component is 197 * set to 255 (1.0). 198 * 199 * @param r 200 * @param g 201 * @param b 202 * 203 * @return uchar4 204 */ 205 _RS_RUNTIME uchar4 __attribute__((const, overloadable)) rsPackColorTo8888(float r, float g, float b); 206 207 /** 208 * Pack floating point (0-1) RGBA values into a uchar4. 209 * 210 * @param r 211 * @param g 212 * @param b 213 * @param a 214 * 215 * @return uchar4 216 */ 217 _RS_RUNTIME uchar4 __attribute__((const, overloadable)) rsPackColorTo8888(float r, float g, float b, float a); 218 219 /** 220 * Pack floating point (0-1) RGB values into a uchar4. The alpha component is 221 * set to 255 (1.0). 222 * 223 * @param color 224 * 225 * @return uchar4 226 */ 227 _RS_RUNTIME uchar4 __attribute__((const, overloadable)) rsPackColorTo8888(float3 color); 228 229 /** 230 * Pack floating point (0-1) RGBA values into a uchar4. 231 * 232 * @param color 233 * 234 * @return uchar4 235 */ 236 _RS_RUNTIME uchar4 __attribute__((const, overloadable)) rsPackColorTo8888(float4 color); 237 238 /** 239 * Unpack a uchar4 color to float4. The resulting float range will be (0-1). 240 * 241 * @param c 242 * 243 * @return float4 244 */ 245 _RS_RUNTIME float4 __attribute__((const)) rsUnpackColor8888(uchar4 c); 246 247 _RS_RUNTIME uchar4 __attribute__((const, overloadable)) rsYuvToRGBA_uchar4(uchar y, uchar u, uchar v); 248 _RS_RUNTIME float4 __attribute__((const, overloadable)) rsYuvToRGBA_float4(uchar y, uchar u, uchar v); 249 250 251 #endif 252
