1 /*!**************************************************************************** 2 3 @file PVRTTrans.h 4 @copyright Copyright (c) Imagination Technologies Limited. 5 @brief Set of functions used for 3D transformations and projections. 6 7 ******************************************************************************/ 8 #ifndef _PVRTTRANS_H_ 9 #define _PVRTTRANS_H_ 10 11 12 /**************************************************************************** 13 ** Typedefs 14 ****************************************************************************/ 15 /*!*************************************************************************** 16 @brief PVRTBOUNDINGBOX is a typedef of a PVRTBOUNDINGBOX_TAG struct. 17 *****************************************************************************/ 18 typedef struct PVRTBOUNDINGBOX_TAG 19 { 20 PVRTVECTOR3 Point[8]; ///< 8 Vertices 21 } PVRTBOUNDINGBOX, *LPPVRTBOUNDINGBOX; 22 23 /**************************************************************************** 24 ** Functions 25 ****************************************************************************/ 26 27 /*!*************************************************************************** 28 @fn PVRTBoundingBoxCompute 29 @param[out] pBoundingBox 30 @param[in] pV 31 @param[in] nNumberOfVertices 32 @brief Calculate the eight vertices that surround an object. 33 This "bounding box" is used later to determine whether 34 the object is visible or not. 35 This function should only be called once to determine the 36 object's bounding box. 37 *****************************************************************************/ 38 void PVRTBoundingBoxCompute( 39 PVRTBOUNDINGBOX * const pBoundingBox, 40 const PVRTVECTOR3 * const pV, 41 const int nNumberOfVertices); 42 43 /*!*************************************************************************** 44 @fn PVRTBoundingBoxComputeInterleaved 45 @param[out] pBoundingBox 46 @param[in] pV 47 @param[in] nNumberOfVertices 48 @param[in] i32Offset 49 @param[in] i32Stride 50 @brief Calculate the eight vertices that surround an object. 51 This "bounding box" is used later to determine whether 52 the object is visible or not. 53 This function should only be called once to determine the 54 object's bounding box. 55 Takes interleaved data using the first vertex's offset 56 and the stride to the next vertex thereafter 57 *****************************************************************************/ 58 void PVRTBoundingBoxComputeInterleaved( 59 PVRTBOUNDINGBOX * const pBoundingBox, 60 const unsigned char * const pV, 61 const int nNumberOfVertices, 62 const int i32Offset, 63 const int i32Stride); 64 65 /*!****************************************************************************** 66 @fn PVRTBoundingBoxIsVisible 67 @param[out] pNeedsZClipping 68 @param[in] pBoundingBox 69 @param[in] pMatrix 70 @return TRUE if the object is visible, FALSE if not. 71 @brief Determine if a bounding box is "visible" or not along the 72 Z axis. 73 If the function returns TRUE, the object is visible and should 74 be displayed (check bNeedsZClipping to know if Z Clipping needs 75 to be done). 76 If the function returns FALSE, the object is not visible and thus 77 does not require to be displayed. 78 bNeedsZClipping indicates whether the object needs Z Clipping 79 (i.e. the object is partially visible). 80 - *pBoundingBox is a pointer to the bounding box structure. 81 - *pMatrix is the World, View & Projection matrices combined. 82 - *bNeedsZClipping is TRUE if Z clipping is required. 83 *****************************************************************************/ 84 bool PVRTBoundingBoxIsVisible( 85 const PVRTBOUNDINGBOX * const pBoundingBox, 86 const PVRTMATRIX * const pMatrix, 87 bool * const pNeedsZClipping); 88 89 /*!*************************************************************************** 90 @fn PVRTTransformVec3Array 91 @param[out] pOut Destination for transformed vectors 92 @param[in] nOutStride Stride between vectors in pOut array 93 @param[in] pV Input vector array 94 @param[in] nInStride Stride between vectors in pV array 95 @param[in] pMatrix Matrix to transform the vectors 96 @param[in] nNumberOfVertices Number of vectors to transform 97 @brief Transform all vertices [X Y Z 1] in pV by pMatrix and 98 store them in pOut. 99 *****************************************************************************/ 100 void PVRTTransformVec3Array( 101 PVRTVECTOR4 * const pOut, 102 const int nOutStride, 103 const PVRTVECTOR3 * const pV, 104 const int nInStride, 105 const PVRTMATRIX * const pMatrix, 106 const int nNumberOfVertices); 107 108 /*!*************************************************************************** 109 @fn PVRTTransformArray 110 @param[out] pTransformedVertex Destination for transformed vectors 111 @param[in] pV Input vector array 112 @param[in] nNumberOfVertices Number of vectors to transform 113 @param[in] pMatrix Matrix to transform the vectors 114 @param[in] fW W coordinate of input vector (e.g. use 1 for position, 0 for normal) 115 @brief Transform all vertices in pVertex by pMatrix and store them in 116 pTransformedVertex 117 - pTransformedVertex is the pointer that will receive transformed vertices. 118 - pVertex is the pointer to untransformed object vertices. 119 - nNumberOfVertices is the number of vertices of the object. 120 - pMatrix is the matrix used to transform the object. 121 *****************************************************************************/ 122 void PVRTTransformArray( 123 PVRTVECTOR3 * const pTransformedVertex, 124 const PVRTVECTOR3 * const pV, 125 const int nNumberOfVertices, 126 const PVRTMATRIX * const pMatrix, 127 const VERTTYPE fW = f2vt(1.0f)); 128 129 /*!*************************************************************************** 130 @fn PVRTTransformArrayBack 131 @param[out] pTransformedVertex 132 @param[in] pVertex 133 @param[in] nNumberOfVertices 134 @param[in] pMatrix 135 @brief Transform all vertices in pVertex by the inverse of pMatrix 136 and store them in pTransformedVertex. 137 - pTransformedVertex is the pointer that will receive transformed vertices. 138 - pVertex is the pointer to untransformed object vertices. 139 - nNumberOfVertices is the number of vertices of the object. 140 - pMatrix is the matrix used to transform the object. 141 *****************************************************************************/ 142 void PVRTTransformArrayBack( 143 PVRTVECTOR3 * const pTransformedVertex, 144 const PVRTVECTOR3 * const pVertex, 145 const int nNumberOfVertices, 146 const PVRTMATRIX * const pMatrix); 147 148 /*!*************************************************************************** 149 @fn PVRTTransformBack 150 @param[out] pOut 151 @param[in] pV 152 @param[in] pM 153 @brief Transform vertex pV by the inverse of pMatrix 154 and store in pOut. 155 *****************************************************************************/ 156 void PVRTTransformBack( 157 PVRTVECTOR4 * const pOut, 158 const PVRTVECTOR4 * const pV, 159 const PVRTMATRIX * const pM); 160 161 /*!*************************************************************************** 162 @fn PVRTTransform 163 @param[out] pOut 164 @param[in] pV 165 @param[in] pM 166 @brief Transform vertex pV by pMatrix and store in pOut. 167 *****************************************************************************/ 168 void PVRTTransform( 169 PVRTVECTOR4 * const pOut, 170 const PVRTVECTOR4 * const pV, 171 const PVRTMATRIX * const pM); 172 173 174 #endif /* _PVRTTRANS_H_ */ 175 176 /***************************************************************************** 177 End of file (PVRTTrans.h) 178 *****************************************************************************/ 179 180
