glamor_vbo.c (7171B)
1 /* 2 * Copyright © 2014 Intel Corporation 3 * 4 * Permission is hereby granted, free of charge, to any person obtaining a 5 * copy of this software and associated documentation files (the "Software"), 6 * to deal in the Software without restriction, including without limitation 7 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 8 * and/or sell copies of the Software, and to permit persons to whom the 9 * Software is furnished to do so, subject to the following conditions: 10 * 11 * The above copyright notice and this permission notice (including the next 12 * paragraph) shall be included in all copies or substantial portions of the 13 * Software. 14 * 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS 21 * IN THE SOFTWARE. 22 */ 23 24 /** 25 * @file glamor_vbo.c 26 * 27 * Helpers for managing streamed vertex buffers used in glamor. 28 */ 29 30 #include "glamor_priv.h" 31 32 /** Default size of the VBO, in bytes. 33 * 34 * If a single request is larger than this size, we'll resize the VBO 35 * and return an appropriate mapping, but we'll resize back down after 36 * that to avoid hogging that memory forever. We don't anticipate 37 * normal usage actually requiring larger VBO sizes. 38 */ 39 #define GLAMOR_VBO_SIZE (512 * 1024) 40 41 /** 42 * Returns a pointer to @size bytes of VBO storage, which should be 43 * accessed by the GL using vbo_offset within the VBO. 44 */ 45 void * 46 glamor_get_vbo_space(ScreenPtr screen, unsigned size, char **vbo_offset) 47 { 48 glamor_screen_private *glamor_priv = glamor_get_screen_private(screen); 49 void *data; 50 51 glamor_make_current(glamor_priv); 52 53 glBindBuffer(GL_ARRAY_BUFFER, glamor_priv->vbo); 54 55 if (glamor_priv->has_buffer_storage) { 56 if (glamor_priv->vbo_size < glamor_priv->vbo_offset + size) { 57 if (glamor_priv->vbo_size) 58 glUnmapBuffer(GL_ARRAY_BUFFER); 59 60 if (size > glamor_priv->vbo_size) { 61 glamor_priv->vbo_size = MAX(GLAMOR_VBO_SIZE, size); 62 63 /* We aren't allowed to resize glBufferStorage() 64 * buffers, so we need to gen a new one. 65 */ 66 glDeleteBuffers(1, &glamor_priv->vbo); 67 glGenBuffers(1, &glamor_priv->vbo); 68 glBindBuffer(GL_ARRAY_BUFFER, glamor_priv->vbo); 69 70 assert(glGetError() == GL_NO_ERROR); 71 glBufferStorage(GL_ARRAY_BUFFER, glamor_priv->vbo_size, NULL, 72 GL_MAP_WRITE_BIT | 73 GL_MAP_PERSISTENT_BIT | 74 GL_MAP_COHERENT_BIT); 75 76 if (glGetError() != GL_NO_ERROR) { 77 /* If the driver failed our coherent mapping, fall 78 * back to the ARB_mbr path. 79 */ 80 glamor_priv->has_buffer_storage = false; 81 glamor_priv->vbo_size = 0; 82 83 return glamor_get_vbo_space(screen, size, vbo_offset); 84 } 85 } 86 87 glamor_priv->vbo_offset = 0; 88 glamor_priv->vb = glMapBufferRange(GL_ARRAY_BUFFER, 89 0, glamor_priv->vbo_size, 90 GL_MAP_WRITE_BIT | 91 GL_MAP_INVALIDATE_BUFFER_BIT | 92 GL_MAP_PERSISTENT_BIT | 93 GL_MAP_COHERENT_BIT); 94 } 95 *vbo_offset = (void *)(uintptr_t)glamor_priv->vbo_offset; 96 data = glamor_priv->vb + glamor_priv->vbo_offset; 97 glamor_priv->vbo_offset += size; 98 } else if (glamor_priv->has_map_buffer_range) { 99 /* Avoid GL errors on GL 4.5 / ES 3.0 with mapping size == 0, 100 * which callers may sometimes pass us (for example, if 101 * clipping leads to zero rectangles left). Prior to that 102 * version, Mesa would sometimes throw errors on unmapping a 103 * zero-size mapping. 104 */ 105 if (size == 0) 106 return NULL; 107 108 if (glamor_priv->vbo_size < glamor_priv->vbo_offset + size) { 109 glamor_priv->vbo_size = MAX(GLAMOR_VBO_SIZE, size); 110 glamor_priv->vbo_offset = 0; 111 glBufferData(GL_ARRAY_BUFFER, 112 glamor_priv->vbo_size, NULL, GL_STREAM_DRAW); 113 } 114 115 data = glMapBufferRange(GL_ARRAY_BUFFER, 116 glamor_priv->vbo_offset, 117 size, 118 GL_MAP_WRITE_BIT | 119 GL_MAP_UNSYNCHRONIZED_BIT | 120 GL_MAP_INVALIDATE_RANGE_BIT); 121 *vbo_offset = (char *)(uintptr_t)glamor_priv->vbo_offset; 122 glamor_priv->vbo_offset += size; 123 glamor_priv->vbo_mapped = TRUE; 124 } else { 125 /* Return a pointer to the statically allocated non-VBO 126 * memory. We'll upload it through glBufferData() later. 127 */ 128 if (glamor_priv->vbo_size < size) { 129 glamor_priv->vbo_size = MAX(GLAMOR_VBO_SIZE, size); 130 free(glamor_priv->vb); 131 glamor_priv->vb = xnfalloc(glamor_priv->vbo_size); 132 } 133 *vbo_offset = NULL; 134 /* We point to the start of glamor_priv->vb every time, and 135 * the vbo_offset determines the size of the glBufferData(). 136 */ 137 glamor_priv->vbo_offset = size; 138 data = glamor_priv->vb; 139 } 140 141 return data; 142 } 143 144 void 145 glamor_put_vbo_space(ScreenPtr screen) 146 { 147 glamor_screen_private *glamor_priv = glamor_get_screen_private(screen); 148 149 glamor_make_current(glamor_priv); 150 151 if (glamor_priv->has_buffer_storage) { 152 /* If we're in the ARB_buffer_storage path, we have a 153 * persistent mapping, so we can leave it around until we 154 * reach the end of the buffer. 155 */ 156 } else if (glamor_priv->has_map_buffer_range) { 157 if (glamor_priv->vbo_mapped) { 158 glUnmapBuffer(GL_ARRAY_BUFFER); 159 glamor_priv->vbo_mapped = FALSE; 160 } 161 } else { 162 glBufferData(GL_ARRAY_BUFFER, glamor_priv->vbo_offset, 163 glamor_priv->vb, GL_DYNAMIC_DRAW); 164 } 165 166 glBindBuffer(GL_ARRAY_BUFFER, 0); 167 } 168 169 void 170 glamor_init_vbo(ScreenPtr screen) 171 { 172 glamor_screen_private *glamor_priv = glamor_get_screen_private(screen); 173 174 glamor_make_current(glamor_priv); 175 176 glGenBuffers(1, &glamor_priv->vbo); 177 glGenVertexArrays(1, &glamor_priv->vao); 178 glBindVertexArray(glamor_priv->vao); 179 } 180 181 void 182 glamor_fini_vbo(ScreenPtr screen) 183 { 184 glamor_screen_private *glamor_priv = glamor_get_screen_private(screen); 185 186 glamor_make_current(glamor_priv); 187 188 glDeleteVertexArrays(1, &glamor_priv->vao); 189 glamor_priv->vao = 0; 190 if (!glamor_priv->has_map_buffer_range) 191 free(glamor_priv->vb); 192 }