LibWeb/WebGL: Implement the EXT_texture_filter_anisotropic extension

Author: https://github.com/Lubrsi
Commit: b15f4424f9
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/6521
Reviewed-by: https://github.com/gmta ✅

Libraries/LibWeb/CMakeLists.txt

@@ -1024,6 +1024,7 @@ set(SOURCES
     WebGL/Extensions/EXTBlendMinMax.cpp
     WebGL/Extensions/EXTColorBufferFloat.cpp
     WebGL/Extensions/EXTRenderSnorm.cpp
+    WebGL/Extensions/EXTTextureFilterAnisotropic.cpp
     WebGL/Extensions/EXTTextureNorm16.cpp
     WebGL/Extensions/OESVertexArrayObject.cpp
     WebGL/Extensions/WebGLCompressedTextureS3tc.cpp

Libraries/LibWeb/Forward.h

@@ -1225,6 +1225,7 @@ class ANGLEInstancedArrays;
 class EXTBlendMinMax;
 class EXTColorBufferFloat;
 class EXTRenderSnorm;
+class EXTTextureFilterAnisotropic;
 class EXTTextureNorm16;
 class OESVertexArrayObject;
 class WebGLCompressedTextureS3tc;

Libraries/LibWeb/WebGL/Extensions/EXTTextureFilterAnisotropic.cpp

@@ -0,0 +1,41 @@
+/*
+ * Copyright (c) 2025, Luke Wilde <luke@ladybird.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibJS/Runtime/Realm.h>
+#include <LibWeb/Bindings/EXTTextureFilterAnisotropicPrototype.h>
+#include <LibWeb/Bindings/Intrinsics.h>
+#include <LibWeb/WebGL/Extensions/EXTTextureFilterAnisotropic.h>
+#include <LibWeb/WebGL/OpenGLContext.h>
+
+namespace Web::WebGL::Extensions {
+
+GC_DEFINE_ALLOCATOR(EXTTextureFilterAnisotropic);
+
+JS::ThrowCompletionOr<GC::Ptr<EXTTextureFilterAnisotropic>> EXTTextureFilterAnisotropic::create(JS::Realm& realm, WebGLRenderingContextBase* context)
+{
+    return realm.create<EXTTextureFilterAnisotropic>(realm, context);
+}
+
+EXTTextureFilterAnisotropic::EXTTextureFilterAnisotropic(JS::Realm& realm, WebGLRenderingContextBase* context)
+    : PlatformObject(realm)
+    , m_context(context)
+{
+    m_context->context().request_extension("GL_EXT_texture_filter_anisotropic");
+}
+
+void EXTTextureFilterAnisotropic::initialize(JS::Realm& realm)
+{
+    WEB_SET_PROTOTYPE_FOR_INTERFACE(EXTTextureFilterAnisotropic);
+    Base::initialize(realm);
+}
+
+void EXTTextureFilterAnisotropic::visit_edges(Visitor& visitor)
+{
+    Base::visit_edges(visitor);
+    visitor.visit(m_context->gc_cell());
+}
+
+}

Libraries/LibWeb/WebGL/Extensions/EXTTextureFilterAnisotropic.h

@@ -0,0 +1,33 @@
+/*
+ * Copyright (c) 2025, Luke Wilde <luke@ladybird.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <LibWeb/Bindings/PlatformObject.h>
+#include <LibWeb/Forward.h>
+#include <LibWeb/WebGL/WebGLRenderingContextBase.h>
+
+namespace Web::WebGL::Extensions {
+
+class EXTTextureFilterAnisotropic : public Bindings::PlatformObject {
+    WEB_PLATFORM_OBJECT(EXTTextureFilterAnisotropic, Bindings::PlatformObject);
+    GC_DECLARE_ALLOCATOR(EXTTextureFilterAnisotropic);
+
+public:
+    static JS::ThrowCompletionOr<GC::Ptr<EXTTextureFilterAnisotropic>> create(JS::Realm&, WebGLRenderingContextBase*);
+
+protected:
+    void initialize(JS::Realm&) override;
+    void visit_edges(Visitor&) override;
+
+private:
+    EXTTextureFilterAnisotropic(JS::Realm&, WebGLRenderingContextBase*);
+
+    // FIXME: It should be GC::Ptr instead of raw pointer, but we need to make WebGLRenderingContextBase inherit from PlatformObject first.
+    WebGLRenderingContextBase* m_context;
+};
+
+}

Libraries/LibWeb/WebGL/Extensions/EXTTextureFilterAnisotropic.idl

@@ -0,0 +1,13 @@
+#import <WebGL/Types.idl>
+
+// https://registry.khronos.org/webgl/extensions/EXT_texture_filter_anisotropic/
+// NOTE: Original EXT_texture_filter_anisotropic name is changed to title case,
+//       so it matches corresponding C++ class name, and does not require
+//       IDL generator to handle snake_case to TitleCase conversion.
+//       Having a different name is totally fine, because LegacyNoInterfaceObject
+//       prevents the name from being exposed to JavaScript.
+[Exposed=(Window,Worker), LegacyNoInterfaceObject]
+interface EXTTextureFilterAnisotropic {
+    const GLenum TEXTURE_MAX_ANISOTROPY_EXT = 0x84FE;
+    const GLenum MAX_TEXTURE_MAX_ANISOTROPY_EXT = 0x84FF;
+};

Libraries/LibWeb/WebGL/WebGL2RenderingContext.cpp

@@ -17,6 +17,7 @@
 #include <LibWeb/WebGL/EventNames.h>
 #include <LibWeb/WebGL/Extensions/EXTColorBufferFloat.h>
 #include <LibWeb/WebGL/Extensions/EXTRenderSnorm.h>
+#include <LibWeb/WebGL/Extensions/EXTTextureFilterAnisotropic.h>
 #include <LibWeb/WebGL/Extensions/EXTTextureNorm16.h>
 #include <LibWeb/WebGL/Extensions/WebGLCompressedTextureS3tc.h>
 #include <LibWeb/WebGL/Extensions/WebGLCompressedTextureS3tcSrgb.h>
@@ -79,6 +80,7 @@ void WebGL2RenderingContext::visit_edges(Cell::Visitor& visitor)
     visitor.visit(m_canvas_element);
     visitor.visit(m_ext_color_buffer_float_extension);
     visitor.visit(m_ext_render_snorm);
+    visitor.visit(m_ext_texture_filter_anisotropic);
     visitor.visit(m_ext_texture_norm16);
     visitor.visit(m_webgl_compressed_texture_s3tc_extension);
     visitor.visit(m_webgl_compressed_texture_s3tc_srgb_extension);
@@ -206,6 +208,15 @@ JS::Object* WebGL2RenderingContext::get_extension(String const& name)
         return m_ext_render_snorm;
     }
 
+    if (name.equals_ignoring_ascii_case("EXT_texture_filter_anisotropic"sv)) {
+        if (!m_ext_texture_filter_anisotropic) {
+            m_ext_texture_filter_anisotropic = MUST(Extensions::EXTTextureFilterAnisotropic::create(realm(), this));
+        }
+
+        VERIFY(m_ext_texture_filter_anisotropic);
+        return m_ext_texture_filter_anisotropic;
+    }
+
     if (name.equals_ignoring_ascii_case("EXT_texture_norm16"sv)) {
         if (!m_ext_texture_norm16) {
             m_ext_texture_norm16 = MUST(Extensions::EXTTextureNorm16::create(realm(), *this));
@@ -230,4 +241,9 @@ WebIDL::Long WebGL2RenderingContext::drawing_buffer_height() const
     return size.height();
 }
 
+bool WebGL2RenderingContext::ext_texture_filter_anisotropic_extension_enabled() const
+{
+    return !!m_ext_texture_filter_anisotropic;
+}
+
 }

Libraries/LibWeb/WebGL/WebGL2RenderingContext.h

@@ -17,7 +17,7 @@
 
 namespace Web::WebGL {
 
-class WebGL2RenderingContext : public Bindings::PlatformObject
+class WebGL2RenderingContext final : public Bindings::PlatformObject
     , public WebGL2RenderingContextImpl {
     WEB_PLATFORM_OBJECT(WebGL2RenderingContext, Bindings::PlatformObject);
     GC_DECLARE_ALLOCATOR(WebGL2RenderingContext);
@@ -51,6 +51,8 @@ public:
     WebIDL::Long drawing_buffer_width() const;
     WebIDL::Long drawing_buffer_height() const;
 
+    virtual bool ext_texture_filter_anisotropic_extension_enabled() const override;
+
 private:
     virtual void initialize(JS::Realm&) override;
 
@@ -84,6 +86,7 @@ private:
     // "Multiple calls to getExtension with the same extension string, taking into account case-insensitive comparison, must return the same object as long as the extension is enabled."
     GC::Ptr<Extensions::EXTColorBufferFloat> m_ext_color_buffer_float_extension;
     GC::Ptr<Extensions::EXTRenderSnorm> m_ext_render_snorm;
+    GC::Ptr<Extensions::EXTTextureFilterAnisotropic> m_ext_texture_filter_anisotropic;
     GC::Ptr<Extensions::EXTTextureNorm16> m_ext_texture_norm16;
     GC::Ptr<Extensions::WebGLCompressedTextureS3tc> m_webgl_compressed_texture_s3tc_extension;
     GC::Ptr<Extensions::WebGLCompressedTextureS3tcSrgb> m_webgl_compressed_texture_s3tc_srgb_extension;

Libraries/LibWeb/WebGL/WebGL2RenderingContextImpl.cpp

@@ -8,6 +8,7 @@
 #define GL_GLEXT_PROTOTYPES 1
 #include <GLES3/gl3.h>
 extern "C" {
+#include <GLES2/gl2ext.h>
 #include <GLES2/gl2ext_angle.h>
 }
 
@@ -394,6 +395,13 @@ void WebGL2RenderingContextImpl::sampler_parameteri(GC::Root<WebGLSampler> sampl
     case GL_TEXTURE_WRAP_S:
     case GL_TEXTURE_WRAP_T:
         break;
+    case GL_TEXTURE_MAX_ANISOTROPY_EXT: {
+        if (ext_texture_filter_anisotropic_extension_enabled())
+            break;
+
+        set_error(GL_INVALID_ENUM);
+        return;
+    }
     default:
         dbgln("Unknown WebGL sampler parameter name: 0x{:04x}", pname);
         set_error(GL_INVALID_ENUM);
@@ -427,6 +435,13 @@ void WebGL2RenderingContextImpl::sampler_parameterf(GC::Root<WebGLSampler> sampl
     case GL_TEXTURE_WRAP_S:
     case GL_TEXTURE_WRAP_T:
         break;
+    case GL_TEXTURE_MAX_ANISOTROPY_EXT: {
+        if (ext_texture_filter_anisotropic_extension_enabled())
+            break;
+
+        set_error(GL_INVALID_ENUM);
+        return;
+    }
     default:
         dbgln("Unknown WebGL sampler parameter name: 0x{:04x}", pname);
         set_error(GL_INVALID_ENUM);
@@ -2571,6 +2586,16 @@ JS::Value WebGL2RenderingContextImpl::get_parameter(WebIDL::UnsignedLong pname)
         glGetInteger64vRobustANGLE(GL_MAX_SERVER_WAIT_TIMEOUT, 1, nullptr, &result);
         return JS::Value(static_cast<double>(result));
     }
+    case GL_MAX_TEXTURE_MAX_ANISOTROPY_EXT: {
+        if (ext_texture_filter_anisotropic_extension_enabled()) {
+            GLfloat result { 0.0f };
+            glGetFloatvRobustANGLE(GL_MAX_TEXTURE_MAX_ANISOTROPY_EXT, 1, nullptr, &result);
+            return JS::Value(result);
+        }
+
+        set_error(GL_INVALID_ENUM);
+        return JS::js_null();
+    }
     default:
         dbgln("Unknown WebGL parameter name: {:x}", pname);
         set_error(GL_INVALID_ENUM);

Libraries/LibWeb/WebGL/WebGLRenderingContext.cpp

@@ -16,6 +16,7 @@
 #include <LibWeb/WebGL/EventNames.h>
 #include <LibWeb/WebGL/Extensions/ANGLEInstancedArrays.h>
 #include <LibWeb/WebGL/Extensions/EXTBlendMinMax.h>
+#include <LibWeb/WebGL/Extensions/EXTTextureFilterAnisotropic.h>
 #include <LibWeb/WebGL/Extensions/OESVertexArrayObject.h>
 #include <LibWeb/WebGL/Extensions/WebGLCompressedTextureS3tc.h>
 #include <LibWeb/WebGL/Extensions/WebGLCompressedTextureS3tcSrgb.h>
@@ -96,6 +97,7 @@ void WebGLRenderingContext::visit_edges(Cell::Visitor& visitor)
     visitor.visit(m_canvas_element);
     visitor.visit(m_angle_instanced_arrays_extension);
     visitor.visit(m_ext_blend_min_max_extension);
+    visitor.visit(m_ext_texture_filter_anisotropic);
     visitor.visit(m_oes_vertex_array_object_extension);
     visitor.visit(m_webgl_compressed_texture_s3tc_extension);
     visitor.visit(m_webgl_compressed_texture_s3tc_srgb_extension);
@@ -206,6 +208,15 @@ JS::Object* WebGLRenderingContext::get_extension(String const& name)
         return m_ext_blend_min_max_extension;
     }
 
+    if (name.equals_ignoring_ascii_case("EXT_texture_filter_anisotropic"sv)) {
+        if (!m_ext_texture_filter_anisotropic) {
+            m_ext_texture_filter_anisotropic = MUST(Extensions::EXTTextureFilterAnisotropic::create(realm(), this));
+        }
+
+        VERIFY(m_ext_texture_filter_anisotropic);
+        return m_ext_texture_filter_anisotropic;
+    }
+
     if (name.equals_ignoring_ascii_case("OES_vertex_array_object"sv)) {
         if (!m_oes_vertex_array_object_extension) {
             m_oes_vertex_array_object_extension = MUST(Extensions::OESVertexArrayObject::create(realm(), *this));
@@ -257,4 +268,9 @@ WebIDL::Long WebGLRenderingContext::drawing_buffer_height() const
     return size.height();
 }
 
+bool WebGLRenderingContext::ext_texture_filter_anisotropic_extension_enabled() const
+{
+    return !!m_ext_texture_filter_anisotropic;
+}
+
 }

Libraries/LibWeb/WebGL/WebGLRenderingContext.h

@@ -16,7 +16,7 @@
 
 namespace Web::WebGL {
 
-class WebGLRenderingContext : public Bindings::PlatformObject
+class WebGLRenderingContext final : public Bindings::PlatformObject
     , public WebGLRenderingContextImpl {
     WEB_PLATFORM_OBJECT(WebGLRenderingContext, Bindings::PlatformObject);
     GC_DECLARE_ALLOCATOR(WebGLRenderingContext);
@@ -50,6 +50,8 @@ public:
     WebIDL::Long drawing_buffer_width() const;
     WebIDL::Long drawing_buffer_height() const;
 
+    virtual bool ext_texture_filter_anisotropic_extension_enabled() const override;
+
 private:
     virtual void initialize(JS::Realm&) override;
 
@@ -83,6 +85,7 @@ private:
     // "Multiple calls to getExtension with the same extension string, taking into account case-insensitive comparison, must return the same object as long as the extension is enabled."
     GC::Ptr<Extensions::ANGLEInstancedArrays> m_angle_instanced_arrays_extension;
     GC::Ptr<Extensions::EXTBlendMinMax> m_ext_blend_min_max_extension;
+    GC::Ptr<Extensions::EXTTextureFilterAnisotropic> m_ext_texture_filter_anisotropic;
     GC::Ptr<Extensions::OESVertexArrayObject> m_oes_vertex_array_object_extension;
     GC::Ptr<Extensions::WebGLCompressedTextureS3tc> m_webgl_compressed_texture_s3tc_extension;
     GC::Ptr<Extensions::WebGLCompressedTextureS3tcSrgb> m_webgl_compressed_texture_s3tc_srgb_extension;

Libraries/LibWeb/WebGL/WebGLRenderingContextBase.h

@@ -26,6 +26,7 @@ public:
     virtual GC::Cell const* gc_cell() const = 0;
     virtual void visit_edges(JS::Cell::Visitor&) = 0;
     virtual OpenGLContext& context() = 0;
+    virtual bool ext_texture_filter_anisotropic_extension_enabled() const = 0;
 
     static Span<float> span_from_float32_list(Float32List& float32_list)
     {

Libraries/LibWeb/WebGL/WebGLRenderingContextImpl.cpp

@@ -1443,6 +1443,16 @@ JS::Value WebGLRenderingContextImpl::get_parameter(WebIDL::UnsignedLong pname)
         auto array_buffer = JS::ArrayBuffer::create(m_realm, move(byte_buffer));
         return JS::Int32Array::create(m_realm, 4, array_buffer);
     }
+    case GL_MAX_TEXTURE_MAX_ANISOTROPY_EXT: {
+        if (ext_texture_filter_anisotropic_extension_enabled()) {
+            GLfloat result { 0.0f };
+            glGetFloatvRobustANGLE(GL_MAX_TEXTURE_MAX_ANISOTROPY_EXT, 1, nullptr, &result);
+            return JS::Value(result);
+        }
+
+        set_error(GL_INVALID_ENUM);
+        return JS::js_null();
+    }
     default:
         dbgln("Unknown WebGL parameter name: {:x}", pname);
         set_error(GL_INVALID_ENUM);

Libraries/LibWeb/idl_files.cmake

@@ -472,6 +472,7 @@ libweb_js_bindings(WebGL/Extensions/ANGLEInstancedArrays)
 libweb_js_bindings(WebGL/Extensions/EXTBlendMinMax)
 libweb_js_bindings(WebGL/Extensions/EXTColorBufferFloat)
 libweb_js_bindings(WebGL/Extensions/EXTRenderSnorm)
+libweb_js_bindings(WebGL/Extensions/EXTTextureFilterAnisotropic)
 libweb_js_bindings(WebGL/Extensions/EXTTextureNorm16)
 libweb_js_bindings(WebGL/Extensions/OESVertexArrayObject)
 libweb_js_bindings(WebGL/Extensions/WebGLCompressedTextureS3tc)