LibWeb/WebGL: Implement getSupportedExtensions()

Libraries/LibWeb/WebGL/OpenGLContext.cpp

@@ -204,4 +204,86 @@ RefPtr<Gfx::PaintingSurface> OpenGLContext::surface()
     return m_painting_surface;
 }
 
+Vector<StringView> s_available_webgl_extensions {
+    // Khronos ratified WebGL Extensions
+    "ANGLE_instanced_arrays"sv,
+    "EXT_blend_minmax"sv,
+    "EXT_frag_depth"sv,
+    "EXT_shader_texture_lod"sv,
+    "EXT_texture_filter_anisotropic"sv,
+    "OES_element_index_uint"sv,
+    "OES_standard_derivatives"sv,
+    "OES_texture_float"sv,
+    "OES_texture_float_linear"sv,
+    "OES_texture_half_float"sv,
+    "OES_texture_half_float_linear"sv,
+    "OES_vertex_array_object"sv,
+    "WEBGL_compressed_texture_s3tc"sv,
+    "WEBGL_debug_renderer_info"sv,
+    "WEBGL_debug_shaders"sv,
+    "WEBGL_depth_texture"sv,
+    "WEBGL_draw_buffers"sv,
+    "WEBGL_lose_context"sv,
+
+    // Community approved WebGL Extensions
+    "EXT_clip_control"sv,
+    "EXT_color_buffer_float"sv,
+    "EXT_color_buffer_half_float"sv,
+    "EXT_conservative_depth"sv,
+    "EXT_depth_clamp"sv,
+    "EXT_disjoint_timer_query"sv,
+    "EXT_disjoint_timer_query_webgl2"sv,
+    "EXT_float_blend"sv,
+    "EXT_polygon_offset_clamp"sv,
+    "EXT_render_snorm"sv,
+    "EXT_sRGB"sv,
+    "EXT_texture_compression_bptc"sv,
+    "EXT_texture_compression_rgtc"sv,
+    "EXT_texture_mirror_clamp_to_edge"sv,
+    "EXT_texture_norm16"sv,
+    "KHR_parallel_shader_compile"sv,
+    "NV_shader_noperspective_interpolation"sv,
+    "OES_draw_buffers_indexed"sv,
+    "OES_fbo_render_mipmap"sv,
+    "OES_sample_variables"sv,
+    "OES_shader_multisample_interpolation"sv,
+    "OVR_multiview2"sv,
+    "WEBGL_blend_func_extended"sv,
+    "WEBGL_clip_cull_distance"sv,
+    "WEBGL_color_buffer_float"sv,
+    "WEBGL_compressed_texture_astc"sv,
+    "WEBGL_compressed_texture_etc"sv,
+    "WEBGL_compressed_texture_etc1"sv,
+    "WEBGL_compressed_texture_pvrtc"sv,
+    "WEBGL_compressed_texture_s3tc_srgb"sv,
+    "WEBGL_multi_draw"sv,
+    "WEBGL_polygon_mode"sv,
+    "WEBGL_provoking_vertex"sv,
+    "WEBGL_render_shared_exponent"sv,
+    "WEBGL_stencil_texturing"sv,
+};
+
+Vector<String> OpenGLContext::get_supported_extensions()
+{
+#ifdef AK_OS_MACOS
+    make_current();
+
+    auto const* extensions_string = reinterpret_cast<char const*>(glGetString(GL_EXTENSIONS));
+    StringView extensions_view(extensions_string, strlen(extensions_string));
+
+    Vector<String> extensions;
+    for (auto const& extension : extensions_view.split_view(' ')) {
+        auto extension_name_without_gl_prefix = extension.substring_view(3);
+        // FIXME: WebGL 1 and WebGL 2 have different sets of available extensions, but for now we simply
+        //        filter out everything that is not listed in https://registry.khronos.org/webgl/extensions/
+        if (s_available_webgl_extensions.contains_slow(extension_name_without_gl_prefix))
+            extensions.append(MUST(String::from_utf8(extension_name_without_gl_prefix)));
+    }
+
+    return extensions;
+#else
+    return {};
+#endif
+}
+
 }

Libraries/LibWeb/WebGL/OpenGLContext.h

@@ -30,6 +30,8 @@ public:
 
     RefPtr<Gfx::PaintingSurface> surface();
 
+    Vector<String> get_supported_extensions();
+
 private:
     NonnullRefPtr<Gfx::SkiaBackendContext> m_skia_backend_context;
     Gfx::IntSize m_size;

Libraries/LibWeb/WebGL/WebGL2RenderingContext.cpp

@@ -145,9 +145,9 @@ void WebGL2RenderingContext::allocate_painting_surface_if_needed()
     context().allocate_painting_surface_if_needed();
 }
 
-Optional<Vector<String>> WebGL2RenderingContext::get_supported_extensions() const
+Optional<Vector<String>> WebGL2RenderingContext::get_supported_extensions()
 {
-    return {};
+    return context().get_supported_extensions();
 }
 
 JS::Object* WebGL2RenderingContext::get_extension(String const&)

Libraries/LibWeb/WebGL/WebGL2RenderingContext.h

@@ -41,7 +41,7 @@ public:
     void set_size(Gfx::IntSize const&);
     void reset_to_default_state();
 
-    Optional<Vector<String>> get_supported_extensions() const;
+    Optional<Vector<String>> get_supported_extensions();
     JS::Object* get_extension(String const& name);
 
     WebIDL::Long drawing_buffer_width() const;

Libraries/LibWeb/WebGL/WebGLRenderingContext.cpp

@@ -161,9 +161,9 @@ void WebGLRenderingContext::allocate_painting_surface_if_needed()
     context().allocate_painting_surface_if_needed();
 }
 
-Optional<Vector<String>> WebGLRenderingContext::get_supported_extensions() const
+Optional<Vector<String>> WebGLRenderingContext::get_supported_extensions()
 {
-    return {};
+    return context().get_supported_extensions();
 }
 
 JS::Object* WebGLRenderingContext::get_extension(String const&)

Libraries/LibWeb/WebGL/WebGLRenderingContext.h

@@ -40,7 +40,7 @@ public:
     void set_size(Gfx::IntSize const&);
     void reset_to_default_state();
 
-    Optional<Vector<String>> get_supported_extensions() const;
+    Optional<Vector<String>> get_supported_extensions();
     JS::Object* get_extension(String const& name);
 
     WebIDL::Long drawing_buffer_width() const;