1 2 /* 3 * Mesa 3-D graphics library 4 * Version: 6.5 5 * 6 * Copyright (C) 1999-2006 Brian Paul 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 "Software"), 10 * to deal in the Software without restriction, including without limitation 11 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 12 * and/or sell copies of the Software, and to permit persons to whom the 13 * Software is furnished to do so, subject to the following conditions: 14 * 15 * The above copyright notice and this permission notice shall be included 16 * in all copies or substantial portions 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 MERCHANTABILITY, 20 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 21 * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN 22 * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 23 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 24 * 25 * Authors: 26 * Keith Whitwell <keith (at) tungstengraphics.com> 27 */ 28 29 /* Helper for drivers which find themselves rendering a range of 30 * indices starting somewhere above zero. Typically the application 31 * is issuing multiple DrawArrays() or DrawElements() to draw 32 * successive primitives layed out linearly in the vertex arrays. 33 * Unless the vertex arrays are all in a VBO, the OpenGL semantics 34 * imply that we need to re-upload the vertex data on each draw call. 35 * In that case, we want to avoid starting the upload at zero, as it 36 * will mean every draw call uploads an increasing amount of not-used 37 * vertex data. Worse - in the software tnl module, all those 38 * vertices will be transformed and lit. 39 * 40 * If we just upload the new data, however, the indices will be 41 * incorrect as we tend to upload each set of vertex data to a new 42 * region. 43 * 44 * This file provides a helper to adjust the arrays, primitives and 45 * indices of a draw call so that it can be re-issued with a min_index 46 * of zero. 47 */ 48 49 #include "main/glheader.h" 50 #include "main/imports.h" 51 #include "main/mtypes.h" 52 53 #include "vbo.h" 54 55 56 #define REBASE(TYPE) \ 57 static void *rebase_##TYPE( const void *ptr, \ 58 GLuint count, \ 59 TYPE min_index ) \ 60 { \ 61 const TYPE *in = (TYPE *)ptr; \ 62 TYPE *tmp_indices = malloc(count * sizeof(TYPE)); \ 63 GLuint i; \ 64 \ 65 for (i = 0; i < count; i++) \ 66 tmp_indices[i] = in[i] - min_index; \ 67 \ 68 return (void *)tmp_indices; \ 69 } 70 71 72 REBASE(GLuint) 73 REBASE(GLushort) 74 REBASE(GLubyte) 75 76 GLboolean vbo_all_varyings_in_vbos( const struct gl_client_array *arrays[] ) 77 { 78 GLuint i; 79 80 for (i = 0; i < VERT_ATTRIB_MAX; i++) 81 if (arrays[i]->StrideB && 82 arrays[i]->BufferObj->Name == 0) 83 return GL_FALSE; 84 85 return GL_TRUE; 86 } 87 88 GLboolean vbo_any_varyings_in_vbos( const struct gl_client_array *arrays[] ) 89 { 90 GLuint i; 91 92 for (i = 0; i < VERT_ATTRIB_MAX; i++) 93 if (arrays[i]->BufferObj->Name != 0) 94 return GL_TRUE; 95 96 return GL_FALSE; 97 } 98 99 /* Adjust primitives, indices and vertex definitions so that min_index 100 * becomes zero. There are lots of reasons for wanting to do this, eg: 101 * 102 * Software tnl: 103 * - any time min_index != 0, otherwise unused vertices lower than 104 * min_index will be transformed. 105 * 106 * Hardware tnl: 107 * - if ib != NULL and min_index != 0, otherwise vertices lower than 108 * min_index will be uploaded. Requires adjusting index values. 109 * 110 * - if ib == NULL and min_index != 0, just for convenience so this doesn't 111 * have to be handled within the driver. 112 * 113 * Hardware tnl with VBO support: 114 * - as above, but only when vertices are not (all?) in VBO's. 115 * - can't save time by trying to upload half a vbo - typically it is 116 * all or nothing. 117 */ 118 void vbo_rebase_prims( struct gl_context *ctx, 119 const struct gl_client_array *arrays[], 120 const struct _mesa_prim *prim, 121 GLuint nr_prims, 122 const struct _mesa_index_buffer *ib, 123 GLuint min_index, 124 GLuint max_index, 125 vbo_draw_func draw ) 126 { 127 struct gl_client_array tmp_arrays[VERT_ATTRIB_MAX]; 128 const struct gl_client_array *tmp_array_pointers[VERT_ATTRIB_MAX]; 129 130 struct _mesa_index_buffer tmp_ib; 131 struct _mesa_prim *tmp_prims = NULL; 132 const struct gl_client_array **saved_arrays = ctx->Array._DrawArrays; 133 void *tmp_indices = NULL; 134 GLuint i; 135 136 assert(min_index != 0); 137 138 if (0) 139 printf("%s %d..%d\n", __FUNCTION__, min_index, max_index); 140 141 142 /* XXX this path is disabled for now. 143 * There's rendering corruption in some apps when it's enabled. 144 */ 145 if (0 && ib && ctx->Extensions.ARB_draw_elements_base_vertex) { 146 /* If we can just tell the hardware or the TNL to interpret our 147 * indices with a different base, do so. 148 */ 149 tmp_prims = (struct _mesa_prim *)malloc(sizeof(*prim) * nr_prims); 150 151 for (i = 0; i < nr_prims; i++) { 152 tmp_prims[i] = prim[i]; 153 tmp_prims[i].basevertex -= min_index; 154 } 155 156 prim = tmp_prims; 157 } else if (ib) { 158 /* Unfortunately need to adjust each index individually. 159 */ 160 GLboolean map_ib = ib->obj->Name && !ib->obj->Pointer; 161 void *ptr; 162 163 if (map_ib) 164 ctx->Driver.MapBufferRange(ctx, 0, ib->obj->Size, GL_MAP_READ_BIT, 165 ib->obj); 166 167 168 ptr = ADD_POINTERS(ib->obj->Pointer, ib->ptr); 169 170 /* Some users might prefer it if we translated elements to 171 * GLuints here. Others wouldn't... 172 */ 173 switch (ib->type) { 174 case GL_UNSIGNED_INT: 175 tmp_indices = rebase_GLuint( ptr, ib->count, min_index ); 176 break; 177 case GL_UNSIGNED_SHORT: 178 tmp_indices = rebase_GLushort( ptr, ib->count, min_index ); 179 break; 180 case GL_UNSIGNED_BYTE: 181 tmp_indices = rebase_GLubyte( ptr, ib->count, min_index ); 182 break; 183 } 184 185 if (map_ib) 186 ctx->Driver.UnmapBuffer(ctx, ib->obj); 187 188 tmp_ib.obj = ctx->Shared->NullBufferObj; 189 tmp_ib.ptr = tmp_indices; 190 tmp_ib.count = ib->count; 191 tmp_ib.type = ib->type; 192 193 ib = &tmp_ib; 194 } 195 else { 196 /* Otherwise the primitives need adjustment. 197 */ 198 tmp_prims = (struct _mesa_prim *)malloc(sizeof(*prim) * nr_prims); 199 200 for (i = 0; i < nr_prims; i++) { 201 /* If this fails, it could indicate an application error: 202 */ 203 assert(prim[i].start >= min_index); 204 205 tmp_prims[i] = prim[i]; 206 tmp_prims[i].start -= min_index; 207 } 208 209 prim = tmp_prims; 210 } 211 212 /* Just need to adjust the pointer values on each incoming array. 213 * This works for VBO and non-vbo rendering and shouldn't pesimize 214 * VBO-based upload schemes. However this may still not be a fast 215 * path for hardware tnl for VBO based rendering as most machines 216 * will be happier if you just specify a starting vertex value in 217 * each primitive. 218 * 219 * For drivers with hardware tnl, you only want to do this if you 220 * are forced to, eg non-VBO indexed rendering with start != 0. 221 */ 222 for (i = 0; i < VERT_ATTRIB_MAX; i++) { 223 tmp_arrays[i] = *arrays[i]; 224 tmp_arrays[i].Ptr += min_index * tmp_arrays[i].StrideB; 225 tmp_array_pointers[i] = &tmp_arrays[i]; 226 } 227 228 /* Re-issue the draw call. 229 */ 230 ctx->Array._DrawArrays = tmp_array_pointers; 231 ctx->NewDriverState |= ctx->DriverFlags.NewArray; 232 233 draw( ctx, 234 prim, 235 nr_prims, 236 ib, 237 GL_TRUE, 238 0, 239 max_index - min_index, 240 NULL ); 241 242 ctx->Array._DrawArrays = saved_arrays; 243 ctx->NewDriverState |= ctx->DriverFlags.NewArray; 244 245 if (tmp_indices) 246 free(tmp_indices); 247 248 if (tmp_prims) 249 free(tmp_prims); 250 } 251 252 253 254