LibWeb/WebGL: Implement EXT_blend_minmax extension

Author: https://github.com/Lubrsi
Commit: https://github.com/LadybirdBrowser/ladybird/commit/948349974c3
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/4270

Libraries/LibWeb/CMakeLists.txt

@@ -864,6 +864,7 @@ set(SOURCES
     WebDriver/TimeoutsConfiguration.cpp
     WebDriver/UserPrompt.cpp
     WebGL/Extensions/ANGLEInstancedArrays.cpp
+    WebGL/Extensions/EXTBlendMinMax.cpp
     WebGL/Extensions/EXTColorBufferFloat.cpp
     WebGL/Extensions/OESVertexArrayObject.cpp
     WebGL/Extensions/WebGLCompressedTextureS3tc.cpp

Libraries/LibWeb/Forward.h

@@ -925,6 +925,7 @@ class WebGLVertexArrayObject;
 
 namespace Web::WebGL::Extensions {
 class ANGLEInstancedArrays;
+class EXTBlendMinMax;
 class EXTColorBufferFloat;
 class OESVertexArrayObject;
 class WebGLCompressedTextureS3tc;

Libraries/LibWeb/WebGL/Extensions/EXTBlendMinMax.cpp

@@ -0,0 +1,42 @@
+/*
+ * Copyright (c) 2025, Luke Wilde <luke@ladybird.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibJS/Runtime/Realm.h>
+#include <LibWeb/Bindings/EXTBlendMinMaxPrototype.h>
+#include <LibWeb/Bindings/Intrinsics.h>
+#include <LibWeb/WebGL/Extensions/EXTBlendMinMax.h>
+#include <LibWeb/WebGL/OpenGLContext.h>
+#include <LibWeb/WebGL/WebGLRenderingContext.h>
+
+namespace Web::WebGL::Extensions {
+
+GC_DEFINE_ALLOCATOR(EXTBlendMinMax);
+
+JS::ThrowCompletionOr<GC::Ptr<EXTBlendMinMax>> EXTBlendMinMax::create(JS::Realm& realm, GC::Ref<WebGLRenderingContext> context)
+{
+    return realm.create<EXTBlendMinMax>(realm, context);
+}
+
+EXTBlendMinMax::EXTBlendMinMax(JS::Realm& realm, GC::Ref<WebGLRenderingContext> context)
+    : PlatformObject(realm)
+    , m_context(context)
+{
+    m_context->context().request_extension("GL_EXT_blend_minmax");
+}
+
+void EXTBlendMinMax::initialize(JS::Realm& realm)
+{
+    Base::initialize(realm);
+    WEB_SET_PROTOTYPE_FOR_INTERFACE(EXTBlendMinMax);
+}
+
+void EXTBlendMinMax::visit_edges(Visitor& visitor)
+{
+    Base::visit_edges(visitor);
+    visitor.visit(m_context);
+}
+
+}

Libraries/LibWeb/WebGL/Extensions/EXTBlendMinMax.h

@@ -0,0 +1,31 @@
+/*
+ * 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>
+
+namespace Web::WebGL::Extensions {
+
+class EXTBlendMinMax : public Bindings::PlatformObject {
+    WEB_PLATFORM_OBJECT(EXTBlendMinMax, Bindings::PlatformObject);
+    GC_DECLARE_ALLOCATOR(EXTBlendMinMax);
+
+public:
+    static JS::ThrowCompletionOr<GC::Ptr<EXTBlendMinMax>> create(JS::Realm&, GC::Ref<WebGLRenderingContext>);
+
+protected:
+    void initialize(JS::Realm&) override;
+    void visit_edges(Visitor&) override;
+
+private:
+    EXTBlendMinMax(JS::Realm&, GC::Ref<WebGLRenderingContext>);
+
+    GC::Ref<WebGLRenderingContext> m_context;
+};
+
+}

Libraries/LibWeb/WebGL/Extensions/EXTBlendMinMax.idl

@@ -0,0 +1,13 @@
+#import <WebGL/Types.idl>
+
+// https://registry.khronos.org/webgl/extensions/EXT_blend_minmax/
+// NOTE: Original EXT_blend_minmax 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 EXTBlendMinMax {
+    const GLenum MIN_EXT = 0x8007;
+    const GLenum MAX_EXT = 0x8008;
+};

Libraries/LibWeb/WebGL/WebGLRenderingContext.cpp

@@ -15,6 +15,7 @@
 #include <LibWeb/Painting/Paintable.h>
 #include <LibWeb/WebGL/EventNames.h>
 #include <LibWeb/WebGL/Extensions/ANGLEInstancedArrays.h>
+#include <LibWeb/WebGL/Extensions/EXTBlendMinMax.h>
 #include <LibWeb/WebGL/Extensions/OESVertexArrayObject.h>
 #include <LibWeb/WebGL/Extensions/WebGLCompressedTextureS3tc.h>
 #include <LibWeb/WebGL/Extensions/WebGLDrawBuffers.h>
@@ -93,6 +94,7 @@ void WebGLRenderingContext::visit_edges(Cell::Visitor& visitor)
     WebGLRenderingContextImpl::visit_edges(visitor);
     visitor.visit(m_canvas_element);
     visitor.visit(m_angle_instanced_arrays_extension);
+    visitor.visit(m_ext_blend_min_max_extension);
     visitor.visit(m_oes_vertex_array_object_extension);
     visitor.visit(m_webgl_compressed_texture_s3tc_extension);
     visitor.visit(m_webgl_draw_buffers_extension);
@@ -202,6 +204,15 @@ JS::Object* WebGLRenderingContext::get_extension(String const& name)
         return m_angle_instanced_arrays_extension;
     }
 
+    if (Infra::is_ascii_case_insensitive_match(name, "EXT_blend_minmax"sv)) {
+        if (!m_ext_blend_min_max_extension) {
+            m_ext_blend_min_max_extension = MUST(Extensions::EXTBlendMinMax::create(realm(), *this));
+        }
+
+        VERIFY(m_ext_blend_min_max_extension);
+        return m_ext_blend_min_max_extension;
+    }
+
     if (Infra::is_ascii_case_insensitive_match(name, "OES_vertex_array_object"sv)) {
         if (!m_oes_vertex_array_object_extension) {
             m_oes_vertex_array_object_extension = MUST(Extensions::OESVertexArrayObject::create(realm(), *this));

Libraries/LibWeb/WebGL/WebGLRenderingContext.h

@@ -82,6 +82,7 @@ private:
     // Extensions
     // "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::OESVertexArrayObject> m_oes_vertex_array_object_extension;
     GC::Ptr<Extensions::WebGLCompressedTextureS3tc> m_webgl_compressed_texture_s3tc_extension;
     GC::Ptr<Extensions::WebGLDrawBuffers> m_webgl_draw_buffers_extension;

Libraries/LibWeb/idl_files.cmake

@@ -395,6 +395,7 @@ libweb_js_bindings(WebAudio/PannerNode)
 libweb_js_bindings(WebAudio/PeriodicWave)
 libweb_js_bindings(WebAudio/StereoPannerNode)
 libweb_js_bindings(WebGL/Extensions/ANGLEInstancedArrays)
+libweb_js_bindings(WebGL/Extensions/EXTBlendMinMax)
 libweb_js_bindings(WebGL/Extensions/EXTColorBufferFloat)
 libweb_js_bindings(WebGL/Extensions/OESVertexArrayObject)
 libweb_js_bindings(WebGL/Extensions/WebGLCompressedTextureS3tc)