1 // 2 // Copyright 2013 The ANGLE Project Authors. All rights reserved. 3 // Use of this source code is governed by a BSD-style license that can be 4 // found in the LICENSE file. 5 // 6 7 // Contants.h: Defines some implementation specific and gl constants 8 9 #ifndef LIBANGLE_CONSTANTS_H_ 10 #define LIBANGLE_CONSTANTS_H_ 11 12 #include "common/platform.h" 13 14 #include <stdint.h> 15 16 namespace gl 17 { 18 19 // The binary cache is currently left disable by default, and the application can enable it. 20 const size_t kDefaultMaxProgramCacheMemoryBytes = 0; 21 22 enum 23 { 24 // Implementation upper limits, real maximums depend on the hardware 25 MAX_SAMPLE_MASK_WORDS = 2, 26 27 MAX_VERTEX_ATTRIBS = 16, 28 MAX_VERTEX_ATTRIB_BINDINGS = 16, 29 30 // Implementation upper limits, real maximums depend on the hardware 31 IMPLEMENTATION_MAX_VARYING_VECTORS = 32, 32 IMPLEMENTATION_MAX_DRAW_BUFFERS = 8, 33 IMPLEMENTATION_MAX_FRAMEBUFFER_ATTACHMENTS = 34 IMPLEMENTATION_MAX_DRAW_BUFFERS + 2, // 2 extra for depth and/or stencil buffers 35 36 // The vast majority of devices support only one dual-source draw buffer 37 IMPLEMENTATION_MAX_DUAL_SOURCE_DRAW_BUFFERS = 1, 38 39 IMPLEMENTATION_MAX_VERTEX_SHADER_UNIFORM_BUFFERS = 16, 40 IMPLEMENTATION_MAX_GEOMETRY_SHADER_UNIFORM_BUFFERS = 16, 41 IMPLEMENTATION_MAX_FRAGMENT_SHADER_UNIFORM_BUFFERS = 16, 42 IMPLEMENTATION_MAX_COMPUTE_SHADER_UNIFORM_BUFFERS = 16, 43 44 // GL_EXT_geometry_shader increases the minimum value of GL_MAX_COMBINED_UNIFORM_BLOCKS to 36. 45 // GL_EXT_tessellation_shader increases the minimum value to 60. 46 IMPLEMENTATION_MAX_COMBINED_SHADER_UNIFORM_BUFFERS = 60, 47 48 // GL_EXT_geometry_shader increases the minimum value of GL_MAX_UNIFORM_BUFFER_BINDINGS to 48. 49 // GL_EXT_tessellation_shader increases the minimum value to 72. 50 IMPLEMENTATION_MAX_UNIFORM_BUFFER_BINDINGS = 72, 51 52 // Transform feedback limits set to the minimum required by the spec. 53 IMPLEMENTATION_MAX_TRANSFORM_FEEDBACK_INTERLEAVED_COMPONENTS = 128, 54 IMPLEMENTATION_MAX_TRANSFORM_FEEDBACK_SEPARATE_ATTRIBS = 4, 55 IMPLEMENTATION_MAX_TRANSFORM_FEEDBACK_SEPARATE_COMPONENTS = 4, 56 IMPLEMENTATION_MAX_TRANSFORM_FEEDBACK_BUFFERS = 4, 57 58 // Maximum number of views which are supported by the implementation of ANGLE_multiview. 59 IMPLEMENTATION_ANGLE_MULTIVIEW_MAX_VIEWS = 4, 60 61 // These are the maximums the implementation can support 62 // The actual GL caps are limited by the device caps 63 // and should be queried from the Context 64 IMPLEMENTATION_MAX_2D_TEXTURE_SIZE = 32768, 65 IMPLEMENTATION_MAX_CUBE_MAP_TEXTURE_SIZE = 32768, 66 IMPLEMENTATION_MAX_3D_TEXTURE_SIZE = 16384, 67 IMPLEMENTATION_MAX_2D_ARRAY_TEXTURE_LAYERS = 2048, 68 69 // 1+log2 of max of MAX_*_TEXTURE_SIZE 70 IMPLEMENTATION_MAX_TEXTURE_LEVELS = 16, 71 72 IMPLEMENTATION_MAX_SHADER_TEXTURES = 32, 73 74 // In ES 3.1 and below, the limit for active textures is 64. 75 IMPLEMENTATION_MAX_ES31_ACTIVE_TEXTURES = 64, 76 77 // In ES 3.2 we need to support a minimum of 96 maximum textures. 78 IMPLEMENTATION_MAX_ACTIVE_TEXTURES = 96, 79 IMPLEMENTATION_MAX_IMAGE_UNITS = IMPLEMENTATION_MAX_ACTIVE_TEXTURES, 80 81 // Maximum number of slots allocated for atomic counter buffers. 82 IMPLEMENTATION_MAX_ATOMIC_COUNTER_BUFFER_BINDINGS = 8, 83 84 // Implementation upper limits, real maximums depend on the hardware. 85 IMPLEMENTATION_MAX_SHADER_STORAGE_BUFFER_BINDINGS = 64, 86 87 // Implementation upper limits of max number of clip distances 88 IMPLEMENTATION_MAX_CLIP_DISTANCES = 32, 89 90 // Implementation upper limit for layered framebuffer layer count 91 IMPLEMENTATION_MAX_FRAMEBUFFER_LAYERS = 256, 92 }; 93 94 namespace limits 95 { 96 // Almost all drivers use 2048 (the minimum value) as GL_MAX_VERTEX_ATTRIB_STRIDE. ANGLE advertizes 97 // the same limit. 98 constexpr uint32_t kMaxVertexAttribStride = 2048; 99 100 // Some of the minimums required by GL, used to detect if the backend meets the minimum requirement. 101 // Currently, there's no need to separate these values per spec version. 102 constexpr uint32_t kMinimumComputeStorageBuffers = 4; 103 104 // OpenGL ES 3.0+ Minimum Values 105 // Table 6.31 MAX_VERTEX_UNIFORM_BLOCKS minimum value = 12 106 // Table 6.32 MAX_FRAGMENT_UNIFORM_BLOCKS minimum value = 12 107 constexpr uint32_t kMinimumShaderUniformBlocks = 12; 108 // Table 6.31 MAX_VERTEX_OUTPUT_COMPONENTS minimum value = 64 109 constexpr uint32_t kMinimumVertexOutputComponents = 64; 110 } // namespace limits 111 112 } // namespace gl 113 114 #endif // LIBANGLE_CONSTANTS_H_ 115