magnum/doc/opengl-support.dox

/*
    This file is part of Magnum.

    Copyright © 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019,
                2020 Vladimír Vondruš <mosra@centrum.cz>

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*/

namespace Magnum {

/** @page opengl-support Support state
@brief List of (un)supported OpenGL features and extensions.

@tableofcontents
@m_footernavigation

@section opengl-support-state OpenGL implementation state

The extension implementation is considered complete if all its defined types,
functions and enum values are exposed through the API, except for features
listed below in @ref opengl-unsupported-features.

All extensions from the below lists are available in the @ref GL::Extensions
namespace and it's possible to check for their availability using
@ref GL::Context::isExtensionSupported(). See its documentation for more
information.

@subsection opengl-support-21 OpenGL 2.1

The core subset of OpenGL 2.1 should be fully implemented, except for the
following:

-   Proxy textures
-   Some forgotten limit queries

@subsection opengl-support-30 OpenGL 3.0

@todo @gl_extension{EXT,texture_array} overlaps with @gl_extension{ARB,framebuffer_object}
@todo Add @gl_extension{ARB,depth_buffer_float} and implement the missing @fn_gl{DepthRange} function, but keep (and implement) @gl_extension{NV,depth_buffer_float} for non-linear depth buffer

@m_class{m-fullwidth}

Extension                                   | Status
------------------------------------------- | ------
GLSL 1.30                                   | done
@fn_gl{ClearBuffer} functions               | done
@gl_extension{ARB,map_buffer_range}         | done
@gl_extension{ARB,color_buffer_float}       | |
@gl_extension{ARB,half_float_pixel}         | done
@gl_extension{ARB,texture_float}            | done
@gl_extension{ARB,depth_buffer_float}       | done
@gl_extension{ARB,texture_rg}               | done
@gl_extension{ARB,vertex_array_object}      | done
@gl_extension{ARB,framebuffer_object}       | done
@gl_extension{ARB,framebuffer_sRGB}         | done
@gl_extension{ARB,half_float_vertex}        | done
@gl_extension{EXT,gpu_shader4}              | done
@gl_extension{EXT,packed_float}             | done
@gl_extension{EXT,texture_array}            | done
@gl_extension{EXT,texture_compression_rgtc} | done
@gl_extension{EXT,texture_shared_exponent}  | done
@gl_extension{EXT,draw_buffers2}            | done (GL 3.0 subset)
@gl_extension{EXT,texture_integer}          | done (GL 3.0 subset)
@gl_extension{EXT,transform_feedback}       | done
`MAGNUM_shader_vertex_id` \n @m_span{m-text m-dim} Pseudo-extension denoting support for the @glsl gl_VertexID @ce GLSL builtin. @m_endspan | done
@gl_extension{NV,depth_buffer_float}        | |
@gl_extension{NV,conditional_render}        | done

@subsection opengl-support-31 OpenGL 3.1

@m_class{m-fullwidth}

Extension                                   | Status
------------------------------------------- | ------
GLSL 1.40                                   | done
@gl_extension{ARB,texture_rectangle}        | done
@gl_extension{ARB,draw_instanced}           | done
@gl_extension{ARB,texture_buffer_object}    | done
@gl_extension{ARB,uniform_buffer_object}    | done except for data layout queries
@gl_extension{ARB,copy_buffer}              | done
@gl_extension{EXT,texture_snorm}            | done
@gl_extension{NV,primitive_restart}         | |

@subsection opengl-support-32 OpenGL 3.2

@m_class{m-fullwidth}

Extension                                   | Status
------------------------------------------- | ------
GLSL 1.50                                   | done
@gl_extension{ARB,geometry_shader4}         | missing some limit queries
@gl_extension{ARB,depth_clamp}              | done
@gl_extension{ARB,draw_elements_base_vertex} | done
@gl_extension{ARB,fragment_coord_conventions} | done (shading language only)
@gl_extension{ARB,provoking_vertex}         | done
@gl_extension{ARB,seamless_cube_map}        | done
@gl_extension{ARB,sync}                     | |
@gl_extension{ARB,texture_multisample}      | missing sample location queries and sample mask
@gl_extension{ARB,vertex_array_bgra}        | done

@subsection opengl-support-33 OpenGL 3.3

@m_class{m-fullwidth}

Extension                                   | Status
------------------------------------------- | ------
GLSL 3.30                                   | done
@gl_extension{ARB,instanced_arrays}         | done
@gl_extension{ARB,blend_func_extended}      | done
@gl_extension{ARB,explicit_attrib_location} | done (shading language only)
@gl_extension{ARB,occlusion_query2}         | done
@gl_extension{ARB,sampler_objects}          | |
@gl_extension{ARB,shader_bit_encoding}      | done (shading language only)
@gl_extension{ARB,texture_rgb10_a2ui}       | done
@gl_extension{ARB,texture_swizzle}          | done
@gl_extension{ARB,timer_query}              | missing direct query
@gl_extension{ARB,vertex_type_2_10_10_10_rev} | done

@subsection opengl-support-40 OpenGL 4.0

@m_class{m-fullwidth}

Extension                                   | Status
------------------------------------------- | ------
GLSL 4.00                                   | done
@gl_extension{ARB,draw_buffers_blend}       | done
@gl_extension{ARB,sample_shading}           | done
@gl_extension{ARB,texture_cube_map_array}   | done
@gl_extension{ARB,texture_gather}           | missing limit queries
@gl_extension{ARB,texture_query_lod}        | done (shading language only)
@gl_extension{ARB,draw_indirect}            | |
@gl_extension{ARB,gpu_shader5}              | missing limit queries
@gl_extension{ARB,gpu_shader_fp64}          | done
@gl_extension{ARB,shader_subroutine}        | |
@gl_extension{ARB,tessellation_shader}      | done except for `MAX_TESS_GEN_LEVEL` and `MAX_TESS_PATCH_COMPONENTS` queries
@gl_extension{ARB,texture_buffer_object_rgb32} | done
@gl_extension{ARB,transform_feedback2}      | done
@gl_extension{ARB,transform_feedback3}      | missing indexed properties query

@subsection opengl-support-41 OpenGL 4.1

@m_class{m-fullwidth}

Extension                                   | Status
------------------------------------------- | ------
GLSL 4.10                                   | done
@gl_extension{ARB,ES2_compatibility}        | only float depth clear
@gl_extension{ARB,get_program_binary}       | |
@gl_extension{ARB,separate_shader_objects}  | only direct uniform binding
@gl_extension{ARB,shader_precision}         | done (shading language only)
@gl_extension{ARB,vertex_attrib_64bit}      | done
@gl_extension{ARB,viewport_array}           | |

@subsection opengl-support-42 OpenGL 4.2

@m_class{m-fullwidth}

Extension                                   | Status
------------------------------------------- | ------
GLSL 4.20                                   | done
@gl_extension{ARB,texture_compression_bptc} | done
@gl_extension{ARB,base_instance}            | done
@gl_extension{ARB,shading_language_420pack} | done (shading language only)
@gl_extension{ARB,transform_feedback_instanced} | done
@gl_extension{ARB,compressed_texture_pixel_storage} | done
@gl_extension{ARB,conservative_depth}       | done (shading language only)
@gl_extension{ARB,internalformat_query}     | |
@gl_extension{ARB,map_buffer_alignment}     | done
@gl_extension{ARB,shader_atomic_counters}   | done
@gl_extension{ARB,shader_image_load_store}  | done
@gl_extension{ARB,shading_language_packing} | done (shading language only)
@gl_extension{ARB,texture_storage}          | done

@subsection opengl-support-43 OpenGL 4.3

@m_class{m-fullwidth}

Extension                                   | Status
------------------------------------------- | ------
GLSL 4.30                                   | done
@gl_extension{ARB,arrays_of_arrays}         | done (shading language only)
@gl_extension{ARB,ES3_compatibility}        | only conservative sample query and compression formats
@gl_extension{ARB,clear_buffer_object}      | |
@gl_extension{ARB,compute_shader}           | done except for indirect dispatch
@gl_extension{ARB,copy_image}               | |
@gl_extension{KHR,debug}                    | missing log retrieval, sync, pipeline and sampler label
@gl_extension{ARB,explicit_uniform_location} | done
@gl_extension{ARB,fragment_layer_viewport}  | done (shading language only)
@gl_extension{ARB,framebuffer_no_attachments} | |
@gl_extension{ARB,internalformat_query2}    | only compressed texture block queries
@gl_extension{ARB,invalidate_subdata}       | done
@gl_extension{ARB,multi_draw_indirect}      | |
@gl_extension{ARB,program_interface_query}  | |
@gl_extension{ARB,robust_buffer_access_behavior} | done (nothing to do)
@gl_extension{ARB,shader_image_size}        | done (shading language only)
@gl_extension{ARB,shader_storage_buffer_object} | missing (unneeded) block binding
@gl_extension{ARB,stencil_texturing}        | done
@gl_extension{ARB,texture_buffer_range}     | done
@gl_extension{ARB,texture_query_levels}     | done (shading language only)
@gl_extension{ARB,texture_storage_multisample} | done
@gl_extension{ARB,texture_view}             | |
@gl_extension{ARB,vertex_attrib_binding}    | |

@subsection opengl-support-44 OpenGL 4.4

@todo Also fallback to @gl_extension{AMD,query_buffer_object}
@todo @gl_extension{AMD,pinned_memory} "fallback" for @gl_extension{ARB,buffer_storage}

@m_class{m-fullwidth}

Extension                                   | Status
------------------------------------------- | ------
GLSL 4.40                                   | done
@def_gl{MAX_VERTEX_ATTRIB_STRIDE}           | |
@gl_extension{ARB,buffer_storage}           | |
@gl_extension{ARB,clear_texture}            | |
@gl_extension{ARB,enhanced_layouts}         | done (shading language only)
@gl_extension{ARB,multi_bind}               | missing sampler and vertex buffer binding
@gl_extension{ARB,query_buffer_object}      | |
@gl_extension{ARB,texture_mirror_clamp_to_edge} | done
@gl_extension{ARB,texture_stencil8}         | done
@gl_extension{ARB,vertex_type_10f_11f_11f_rev} | done

@subsection opengl-support-45 OpenGL 4.5

@m_class{m-fullwidth}

Extension                                   | Status
------------------------------------------- | ------
GLSL 4.50                                   | done
@gl_extension{ARB,ES3_1_compatibility}      | done
@gl_extension{ARB,clip_control}             | |
@gl_extension{ARB,conditional_render_inverted} | done
@gl_extension{ARB,cull_distance}            | done
@gl_extension{ARB,derivative_control}       | done (shading language only)
@gl_extension{ARB,direct_state_access}      | done for implemented functionality
@gl_extension{ARB,get_texture_sub_image}    | done
@gl_extension{ARB,shader_texture_image_samples} | done (shading language only)
@gl_extension{ARB,texture_barrier}          | done
@gl_extension{KHR,context_flush_control}    | |
@gl_extension{KHR,robustness}               | |

@subsection opengl-support-46 OpenGL 4.6

@m_class{m-fullwidth}

Extension                                   | Status
------------------------------------------- | ------
GLSL 4.60                                   | done
@gl_extension{ARB,indirect_parameters}      | |
@gl_extension{ARB,shader_draw_parameters}   | done (shading language only)
@gl_extension{ARB,shader_group_vote}        | done (shading language only)
@gl_extension{ARB,pipeline_statistics_query} | done
@gl_extension{ARB,transform_feedback_overflow_query} | done
@gl_extension{ARB,shader_atomic_counter_ops} | done (shading language only)
@gl_extension{ARB,gl_spirv}                 | |
@gl_extension{ARB,polygon_offset_clamp}     | |
@gl_extension{ARB,spirv_extensions}         | |
@gl_extension{ARB,texture_filter_anisotropic} | done
@gl_extension{KHR,no_error}                 | done

@subsection opengl-support-extensions ARB / Khronos OpenGL extensions

@m_class{m-fullwidth}

Extension                                   | Status
------------------------------------------- | ------
@gl_extension{ARB,robustness}               | done
@gl_extension{KHR,texture_compression_astc_hdr} | done
@gl_extension{ARB,robustness_isolation}     | done
@gl_extension{ARB,bindless_texture}         | |
@gl_extension{ARB,compute_variable_group_size} | |
@gl_extension{ARB,seamless_cubemap_per_texture} | |
@gl_extension{ARB,sparse_texture}           | |
@gl_extension{ARB,sparse_buffer}            | |
@gl_extension{ARB,ES3_2_compatibility}      | |
@gl_extension{ARB,sample_locations}         | |
@gl_extension2{KHR,texture_compression_astc_ldr,KHR_texture_compression_astc_hdr} | done
@gl_extension{KHR,robust_buffer_access_behavior} | done (nothing to do)
@gl_extension{KHR,blend_equation_advanced}  | done
@gl_extension2{KHR,blend_equation_advanced_coherent,KHR_blend_equation_advanced} | done
@gl_extension{KHR,texture_compression_astc_sliced_3d} | done (nothing to do)

@subsection opengl-support-extensions-vendor Vendor OpenGL extensions

@todo @gl_extension{ARB,sparse_texture}, @gl_extension{ARB,bindless_texture} + their vendor equivalents
@todo @gl_extension{ATI,meminfo}, @gl_extension{NVX,gpu_memory_info}, GPU temperature
@todo @gl_extension{AMD,performance_monitor}, @gl_extension{INTEL,performance_query}

@m_class{m-fullwidth}

Extension                                   | Status
------------------------------------------- | ------
@gl_extension{AMD,transform_feedback3_lines_triangles} | done (nothing to do)
@gl_extension{AMD,sample_positions}         | |
@gl_extension{AMD,vertex_shader_layer}      | done (shading language only)
@gl_extension{AMD,shader_trinary_minmax}    | done (shading language only)
@gl_extension{AMD,shader_explicit_vertex_parameter} | done (shading language only)
@gl_extension{ATI,texture_mirror_once}      | done (GL 4.4 subset)
@gl_extension{EXT,texture_filter_anisotropic} | done
@gl_extension{EXT,texture_compression_s3tc} | done
@gl_extension{EXT,texture_mirror_clamp}     | only GL 4.4 subset
@gl_extension{EXT,texture_compression_dxt1} | done
@gl_extension{EXT,texture_sRGB_decode}      | done
@gl_extension{EXT,shader_integer_mix}       | done (shading language only)
@gl_extension{EXT,debug_label}              | missing pipeline and sampler label
@gl_extension{EXT,debug_marker}             | done
@gl_extension{EXT,texture_sRGB_R8}          | done
@gl_extension{GREMEDY,string_marker}        | done
@gl_extension{NV,sample_locations}          | |
@gl_extension{NV,fragment_shader_barycentric} | done (shading language only)
@gl_extension{OVR,multiview}                | |
@gl_extension{OVR,multiview2}               | |

@subsection opengl-support-es20 OpenGL ES 2.0

Features that have their equivalents implemented in desktop version are
supported. ESSL 1.00 is supported.

@subsection opengl-support-es30 OpenGL ES 3.0

Features that have their equivalents implemented in desktop version are
supported. ESSL 3.00 is supported.

@subsection opengl-support-es31 OpenGL ES 3.1

Features that have their equivalents implemented in desktop version are
supported. ESSL 3.10 is supported.

@subsection opengl-support-es32 OpenGL ES 3.2

Features that have their equivalents implemented in desktop version are
supported. ESSL 3.20 is supported.

@m_class{m-fullwidth}

Extension                                   | Status
------------------------------------------- | ------
@gl_extension{EXT,color_buffer_half_float}  | |
@gl_extension{EXT,color_buffer_float}       | |
@gl_extension{EXT,copy_image}               | |
@gl_extension{EXT,draw_buffers_indexed}     | done
@gl_extension{EXT,geometry_shader}          | missing some ES-specific limit queries
@gl_extension{EXT,gpu_shader5}              | done (shading language only)
@gl_extension{EXT,shader_io_blocks}         | done (shading language only)
@gl_extension{EXT,tessellation_shader}      | done except for `MAX_TESS_GEN_LEVEL` and `MAX_TESS_PATCH_COMPONENTS` queries
@gl_extension{EXT,texture_border_clamp}     | done
@gl_extension{EXT,texture_buffer}           | done
@gl_extension{EXT,texture_cube_map_array}   | done
@gl_extension{EXT,primitive_bounding_box}   | |
@gl_extension2{KHR,texture_compression_astc_ldr,KHR_texture_compression_astc_hdr} | done
@gl_extension{KHR,debug}                    | see above
@gl_extension{KHR,blend_equation_advanced}  | done
@gl_extension{KHR,robustness}               | |
@gl_extension{KHR,robust_buffer_access_behavior} | done (nothing to do)
@gl_extension{OES,sample_shading}           | done
@gl_extension{OES,sample_variables}         | done (shading language only)
@gl_extension{OES,shader_image_atomic}      | done (shading language only)
@gl_extension{OES,shader_multisample_interpolation} | |
@gl_extension{OES,texture_stencil8}         | done
@gl_extension{OES,texture_storage_multisample_2d_array} | done

@subsection opengl-support-es30-extensions OpenGL ES 2.0 extensions to match ES 3.0 functionality

Unless said otherwise, these are not exposed in the @ref GL::Extensions
namespace on @ref MAGNUM_TARGET_GLES2 "OpenGL ES 3.0 builds".

@m_class{m-fullwidth}

Extension                                   | Status
------------------------------------------- | ------
@gl_extension{ANGLE,framebuffer_blit}       | done
@gl_extension{ANGLE,framebuffer_multisample} | done
@gl_extension{ANGLE,instanced_arrays}       | done
@gl_extension{ANGLE,depth_texture}          | done
@gl_extension{APPLE,framebuffer_multisample} | done (ES 3.0 subset)
@gl_extension{APPLE,texture_max_level}      | done
@gl_extension{ARM,rgba8}                    | done
@gl_extension{EXT,texture_type_2_10_10_10_REV} | done
@gl_extension{EXT,discard_framebuffer}      | done
@gl_extension{EXT,blend_minmax}             | done
@gl_extension{EXT,shader_texture_lod}       | done (shading language only)
@gl_extension{EXT,unpack_subimage}          | done
@gl_extension{EXT,occlusion_query_boolean}  | done
@gl_extension{EXT,shadow_samplers}          | done
@gl_extension{EXT,texture_rg}               | done
@gl_extension{EXT,sRGB}                     | done
@gl_extension{EXT,texture_storage}          | done
@gl_extension{EXT,map_buffer_range}         | done
@gl_extension{EXT,draw_buffers}             | done
@gl_extension{EXT,instanced_arrays}         | done
@gl_extension{EXT,draw_instanced}           | done
`MAGNUM_shader_vertex_id` \n @m_span{m-text m-dim} Pseudo-extension denoting support for the @glsl gl_VertexID @ce \n GLSL builtin. Exposed on ES3 builds only. @m_endspan | done
@gl_extension{NV,draw_buffers}              | done
@gl_extension{NV,fbo_color_attachments}     | done
@gl_extension{NV,read_buffer}               | done
@gl_extension{NV,pack_subimage}             | done
@gl_extension{NV,draw_instanced}            | done
@gl_extension{NV,framebuffer_blit}          | done
@gl_extension{NV,framebuffer_multisample}   | done
@gl_extension{NV,instanced_arrays}          | done
@gl_extension{NV,shadow_samplers_array}     | done (shading language only)
@gl_extension{NV,shadow_samplers_cube}      | done (shading language only)
@gl_extension{OES,depth24}                  | done
@gl_extension{OES,element_index_uint}       | done
@gl_extension{OES,fbo_render_mipmap}        | done
@gl_extension{OES,rgb8_rgba8}               | done (desktop-compatible subset)
@gl_extension{OES,texture_3D}               | done
@gl_extension2{OES,texture_half_float_linear,OES_texture_float_linear} | done
@gl_extension2{OES,texture_half_float,OES_texture_float} | done
@gl_extension{OES,texture_float}            | done
@gl_extension{OES,texture_npot}             | done (nothing to do)
@gl_extension{OES,vertex_half_float}        | done
@gl_extension{OES,packed_depth_stencil}     | done
@gl_extension{OES,depth_texture}            | done
@gl_extension{OES,standard_derivatives}     | done
@gl_extension{OES,vertex_array_object}      | done
@gl_extension{OES,required_internalformat}  | done (desktop-compatible subset)
@gl_extension{OES,surfaceless_context}      | done

@subsection opengl-support-es-extensions OpenGL ES extensions

@todo @gl_extension{NV,non_square_matrices}
@todo Support also IMG_multisampled_render_to_texture? It has different enum
    values (!)

@m_class{m-fullwidth}

Extension                                   | Status
------------------------------------------- | ------
@gl_extension{ANDROID,extension_pack_es31a} | done (nothing to do)
@gl_extension2{ANGLE,texture_compression_dxt1,ANGLE_texture_compression_dxt} | done
@gl_extension2{ANGLE,texture_compression_dxt3,ANGLE_texture_compression_dxt} | done
@gl_extension2{ANGLE,texture_compression_dxt5,ANGLE_texture_compression_dxt} | done
@gl_extension{APPLE,texture_format_BGRA8888} | done
@gl_extension{APPLE,clip_distance}          | done
@gl_extension{ARM,shader_framebuffer_fetch} | missing renderer setup and limit query
@gl_extension{ARM,shader_framebuffer_fetch_depth_stencil} | done (shading language only)
@gl_extension{EXT,texture_filter_anisotropic} | done
@gl_extension{EXT,texture_compression_dxt1} | done
@gl_extension{EXT,texture_format_BGRA8888}  | done
@gl_extension{EXT,read_format_bgra}         | done
@gl_extension{EXT,multi_draw_arrays}        | done
@gl_extension{EXT,debug_label}              | see above
@gl_extension{EXT,debug_marker}             | done
@gl_extension2{EXT,separate_shader_objects,EXT_separate_shader_objects.gles} | only direct uniform binding
@gl_extension{EXT,multisampled_render_to_texture} | only renderbuffer storage
@gl_extension{EXT,robustness}               | done
@gl_extension{EXT,shader_framebuffer_fetch} | missing limit query
@gl_extension{EXT,disjoint_timer_query}     | only time elapsed query
@gl_extension{EXT,texture_sRGB_decode}      | done
@gl_extension{EXT,sRGB_write_control}       | done
@gl_extension{EXT,texture_compression_s3tc} | done
@gl_extension{EXT,pvrtc_sRGB}               | done
@gl_extension{EXT,shader_integer_mix}       | done (shading language only)
@gl_extension{EXT,texture_norm16}           | done
@gl_extension{EXT,texture_sRGB_R8}          | done
@gl_extension{EXT,texture_sRGB_RG8}         | done
@gl_extension{EXT,polygon_offset_clamp}     | |
@gl_extension{EXT,clip_cull_distance}       | done
@gl_extension{EXT,texture_compression_rgtc} | done
@gl_extension{EXT,texture_compression_bptc} | done
@gl_extension{EXT,texture_compression_s3tc_srgb} | done
@gl_extension{IMG,texture_compression_pvrtc} | done
@gl_extension2{KHR,texture_compression_astc_hdr,KHR_texture_compression_astc_hdr} | done
@gl_extension2{KHR,blend_equation_advanced_coherent,KHR_blend_equation_advanced} | done
@gl_extension{KHR,context_flush_control}    | |
@gl_extension{KHR,no_error}                 | done
@gl_extension{KHR,texture_compression_astc_sliced_3d} | done (nothing to do)
@gl_extension2{NV,read_buffer_front,NV_read_buffer} | done
@gl_extension2{NV,read_depth,NV_read_depth_stencil} | done
@gl_extension2{NV,read_stencil,NV_read_depth_stencil} | done
@gl_extension{NV,read_depth_stencil}        | done
@gl_extension{NV,texture_border_clamp}      | done
@gl_extension{NV,shader_noperspective_interpolation} | done (shading language only)
@gl_extension{NV,sample_locations}          | |
@gl_extension{NV,polygon_mode}              | done
@gl_extension{OES,depth32}                  | done
@gl_extension{OES,mapbuffer}                | done
@gl_extension{OES,stencil1}                 | done
@gl_extension{OES,stencil4}                 | done
@gl_extension{OES,texture_float_linear}     | done
@gl_extension{OVR,multiview}                | |
@gl_extension{OVR,multiview2}               | |

@subsection opengl-support-webgl10 WebGL 1.0

Features that have their equivalents implemented in OpenGL ES 2.0 are
supported.

@subsection opengl-support-webgl20 WebGL 2.0

Features that have their equivalents implemented in OpenGL ES 3.0 are
supported.

@subsection opengl-support-webgl20-extensions WebGL 1.0 extensions to match WebGL 2.0 functionality

Unless said otherwise, these are not available in the @ref GL::Extensions
namespace on @ref MAGNUM_TARGET_GLES2 "WebGL 2.0 builds".

@m_class{m-fullwidth}

Extension                                   | Status
------------------------------------------- | ------
@webgl_extension{ANGLE,instanced_arrays}    | done
@webgl_extension{EXT,color_buffer_half_float} | |
@webgl_extension{EXT,blend_minmax}          | done
@webgl_extension{EXT,shader_texture_lod}    | done (shading language only)
`MAGNUM_shader_vertex_id` \n @m_span{m-text m-dim} Pseudo-extension denoting support for the @glsl gl_VertexID @ce \n GLSL builtin. Exposed on WebGL 2 builds only. @m_endspan | done
@webgl_extension{OES,texture_float}         | done
@webgl_extension{OES,texture_half_float}    | done
@webgl_extension{OES,standard_derivatives}  | done
@webgl_extension{OES,vertex_array_object}   | done
@webgl_extension{OES,element_index_uint}    | done
@webgl_extension{OES,texture_half_float_linear} | done
@webgl_extension{OES,fbo_render_mipmap}     | done
@webgl_extension{WEBGL,depth_texture}       | done
@webgl_extension{WEBGL,color_buffer_float}  | |
@webgl_extension{WEBGL,draw_buffers}        | done

@attention @webgl_extension{EXT,color_buffer_half_float} and
    @webgl_extension{WEBGL,color_buffer_float} are not part of WebGL 2.0, but
    are included in this table because they are subsumed by
    @webgl_extension{EXT,color_buffer_float} in WebGL 2.0.

@subsection opengl-support-webgl-extensions WebGL extensions to match desktop functionality

@m_class{m-fullwidth}

Extension                                   | Status
------------------------------------------- | ------
@webgl_extension{EXT,texture_filter_anisotropic} | done
@webgl_extension{EXT,sRGB}                  | done
@webgl_extension{EXT,disjoint_timer_query}  | only time elapsed query
@webgl_extension{EXT,color_buffer_float}    | |
@webgl_extension{EXT,texture_compression_rgtc} | done
@webgl_extension{EXT,texture_compression_bptc} | done
@webgl_extension{EXT,clip_cull_distance}    | done
@webgl_extension{EXT,texture_norm16}        | done
@webgl_extension{EXT,draw_buffers_indexed}  | done
@webgl_extension{OES,texture_float_linear}  | done
@webgl_extension{OVR,multiview2}            | |
@webgl_extension{WEBGL,compressed_texture_s3tc} | done
@webgl_extension{WEBGL,compressed_texture_pvrtc} | done
@webgl_extension{WEBGL,compressed_texture_astc} | done
@webgl_extension{WEBGL,compressed_texture_s3tc_srgb} | done
@webgl_extension{WEBGL,blend_equation_advanced_coherent} | done

@section opengl-unsupported Unsupported OpenGL features

Some functionality, which is either soon-to-be deprecated or isn't proven to
add any performance gains, is not supported in Magnum. See also
@ref opengl-deprecated.

@subsection opengl-unsupported-features Unsupported features

-   API that is not part of core profile or is marked as deprecated (but still
    supported in core profile) in the latest version of OpenGL specification is
    not supported. The only exception are features that are needed for some
    OpenGL ES 2.0 implementations (such as luminance texture formats).
-   State queries (various `glIs*()`, `glGet*()` functions) are not supported.
    Magnum API is designed to prevent the need for majority of them, many of
    them are tracked internally to avoid redundant state changes and in many
    cases it is easier to set the state to some value rather than query it and
    then decide on the result. For detailed state introspection please use
    external debugger (such as ApiTrace), which is more convenient to use than
    manual queries. Queries of implementation-defined values (various limits
    etc.) and queries of generated values (buffer data, texture data) are
    supported.
-   Line and polygon smoothing (`GL_LINE_SMOOTH`, `GL_POLYGON_SMOOTH`) and
    related functions are not supported, as the driver might do it in software
    with serious performance drops. Multisampling is far superior solution.
-   Fixed precision data types (`GL_FIXED` in OpenGL ES) are not supported, as
    they occupy the same memory as floats and they aren't faster than floats on
    current hardware anymore. They are also not available in WebGL or desktop
    GL.
-   Shader compiler is assumed to be present (`GL_SHADER_COMPILER` returning
    true), as all desktop GL implementations and also ES3 are required to
    support it.
-   Querying shader attribute locations using @fn_gl_keyword{GetAttribLocation}
    and other resources using @fn_gl_keyword{GetProgramResource},
    @fn_gl_keyword{GetProgramResourceIndex},
    @fn_gl_keyword{GetProgramResourceLocation},
    @fn_gl_keyword{GetProgramResourceLocationIndex}
    or @fn_gl_keyword{GetProgramResourceName} (as opposed to setting them) is
    not supported, as newer GL versions encourage setting them explicitly in
    shader code.
-   Direct vertex data specification (as opposed to using buffers) is not
    supported, as it encourages bad practices.
-   @fn_gl{PixelStore} with @def_gl{PACK_SWAP_BYTES} / @def_gl{UNPACK_SWAP_BYTES}.
    Too much burden imposed on every API that deals with pixel storage. Use
    @ref Corrade::Utility::Endianness instead. Note that this state is also not
    tracked, so it won't get reset in case a 3rd party code enables it.

@subsection opengl-unsupported-extensions Unsupported ARB / Khronos extensions

-   @gl_extension{ARB,shading_language_include} is overly complicated and
    supported exclusively by NVidia
-   @gl_extension{ARB,cl_event} seems to be not supported anywhere
-   @gl_extension{ARB,shader_stencil_export} is supported exclusively by AMD
-   @gl_extension{EXT,texture_compression_latc} is superseded by
    @gl_extension{EXT,texture_compression_rgtc}, available in OpenGL 3.0.

@subsection opengl-unsupported-extensions-vendor Unsupported vendor extensions

-   @gl_extension{INTEL,map_texture} negatively affects texture access
    performance. Combination of buffer mapping and pixel buffers might be of
    the same or better performance, without affecting texture access speed.
-   @gl_extension{NV,draw_texture} can be done with framebuffer blitting and
    doesn't make any full-screen postprocessing easier, as shaders are
    excluded.
-   @gl_extension{IMG,texture_compression_pvrtc2} OpenGL ES extension is not
    supported as there is no equivalent in WebGL nor Metal and
    [all hardware having support for it suppors other formats as well](https://forums.developer.apple.com/thread/38454).
*/

/** @page opengl-deprecated Deprecated OpenGL API list

@m_footernavigation

See also @ref opengl-unsupported and @ref deprecated.

*/

/** @page deprecated Deprecated list

See also @ref opengl-deprecated.

*/

}