LibWeb/WebGL: Implement the WEBGL_compressed_texture_s3tc_srgb extension

Author: https://github.com/Lubrsi
Commit: d08915a0cd
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/6521
Reviewed-by: https://github.com/gmta ✅

Libraries/LibWeb/CMakeLists.txt

@@ -1027,6 +1027,7 @@ set(SOURCES
     WebGL/Extensions/EXTTextureNorm16.cpp
     WebGL/Extensions/OESVertexArrayObject.cpp
     WebGL/Extensions/WebGLCompressedTextureS3tc.cpp
+    WebGL/Extensions/WebGLCompressedTextureS3tcSrgb.cpp
     WebGL/Extensions/WebGLDrawBuffers.cpp
     WebGL/Extensions/WebGLVertexArrayObjectOES.cpp
     WebGL/OpenGLContext.cpp

Libraries/LibWeb/Forward.h

@@ -1228,6 +1228,7 @@ class EXTRenderSnorm;
 class EXTTextureNorm16;
 class OESVertexArrayObject;
 class WebGLCompressedTextureS3tc;
+class WebGLCompressedTextureS3tcSrgb;
 class WebGLDrawBuffers;
 class WebGLVertexArrayObjectOES;
 

Libraries/LibWeb/WebGL/Extensions/WebGLCompressedTextureS3tcSrgb.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/Intrinsics.h>
+#include <LibWeb/Bindings/WebGLCompressedTextureS3tcSrgbPrototype.h>
+#include <LibWeb/WebGL/Extensions/WebGLCompressedTextureS3tcSrgb.h>
+#include <LibWeb/WebGL/OpenGLContext.h>
+
+namespace Web::WebGL::Extensions {
+
+GC_DEFINE_ALLOCATOR(WebGLCompressedTextureS3tcSrgb);
+
+JS::ThrowCompletionOr<GC::Ptr<WebGLCompressedTextureS3tcSrgb>> WebGLCompressedTextureS3tcSrgb::create(JS::Realm& realm, WebGLRenderingContextBase* context)
+{
+    return realm.create<WebGLCompressedTextureS3tcSrgb>(realm, context);
+}
+
+WebGLCompressedTextureS3tcSrgb::WebGLCompressedTextureS3tcSrgb(JS::Realm& realm, WebGLRenderingContextBase* context)
+    : PlatformObject(realm)
+    , m_context(context)
+{
+    m_context->context().request_extension("GL_EXT_texture_compression_s3tc_srgb");
+}
+
+void WebGLCompressedTextureS3tcSrgb::initialize(JS::Realm& realm)
+{
+    WEB_SET_PROTOTYPE_FOR_INTERFACE(WebGLCompressedTextureS3tcSrgb);
+    Base::initialize(realm);
+}
+
+void WebGLCompressedTextureS3tcSrgb::visit_edges(Visitor& visitor)
+{
+    Base::visit_edges(visitor);
+    visitor.visit(m_context->gc_cell());
+}
+
+}

Libraries/LibWeb/WebGL/Extensions/WebGLCompressedTextureS3tcSrgb.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 WebGLCompressedTextureS3tcSrgb : public Bindings::PlatformObject {
+    WEB_PLATFORM_OBJECT(WebGLCompressedTextureS3tcSrgb, Bindings::PlatformObject);
+    GC_DECLARE_ALLOCATOR(WebGLCompressedTextureS3tcSrgb);
+
+public:
+    static JS::ThrowCompletionOr<GC::Ptr<WebGLCompressedTextureS3tcSrgb>> create(JS::Realm&, WebGLRenderingContextBase*);
+
+protected:
+    void initialize(JS::Realm&) override;
+    void visit_edges(Visitor&) override;
+
+private:
+    WebGLCompressedTextureS3tcSrgb(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/WebGLCompressedTextureS3tcSrgb.idl

@@ -0,0 +1,16 @@
+#import <WebGL/Types.idl>
+
+// https://registry.khronos.org/webgl/extensions/WEBGL_compressed_texture_s3tc_srgb/
+// NOTE: Original WEBGL_compressed_texture_s3tc_srgb 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 WebGLCompressedTextureS3tcSrgb {
+    // Compressed Texture Formats
+    const GLenum COMPRESSED_SRGB_S3TC_DXT1_EXT = 0x8C4C;
+    const GLenum COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT = 0x8C4D;
+    const GLenum COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT = 0x8C4E;
+    const GLenum COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT = 0x8C4F;
+};

Libraries/LibWeb/WebGL/WebGL2RenderingContext.cpp

@@ -19,6 +19,7 @@
 #include <LibWeb/WebGL/Extensions/EXTRenderSnorm.h>
 #include <LibWeb/WebGL/Extensions/EXTTextureNorm16.h>
 #include <LibWeb/WebGL/Extensions/WebGLCompressedTextureS3tc.h>
+#include <LibWeb/WebGL/Extensions/WebGLCompressedTextureS3tcSrgb.h>
 #include <LibWeb/WebGL/OpenGLContext.h>
 #include <LibWeb/WebGL/WebGL2RenderingContext.h>
 #include <LibWeb/WebGL/WebGLContextEvent.h>
@@ -80,6 +81,7 @@ void WebGL2RenderingContext::visit_edges(Cell::Visitor& visitor)
     visitor.visit(m_ext_render_snorm);
     visitor.visit(m_ext_texture_norm16);
     visitor.visit(m_webgl_compressed_texture_s3tc_extension);
+    visitor.visit(m_webgl_compressed_texture_s3tc_srgb_extension);
 }
 
 void WebGL2RenderingContext::present()
@@ -177,6 +179,15 @@ JS::Object* WebGL2RenderingContext::get_extension(String const& name)
         return m_webgl_compressed_texture_s3tc_extension;
     }
 
+    if (name.equals_ignoring_ascii_case("WEBGL_compressed_texture_s3tc_srgb"sv)) {
+        if (!m_webgl_compressed_texture_s3tc_srgb_extension) {
+            m_webgl_compressed_texture_s3tc_srgb_extension = MUST(Extensions::WebGLCompressedTextureS3tcSrgb::create(realm(), this));
+        }
+
+        VERIFY(m_webgl_compressed_texture_s3tc_srgb_extension);
+        return m_webgl_compressed_texture_s3tc_srgb_extension;
+    }
+
     if (name.equals_ignoring_ascii_case("EXT_color_buffer_float"sv)) {
         if (!m_ext_color_buffer_float_extension) {
             m_ext_color_buffer_float_extension = MUST(Extensions::EXTColorBufferFloat::create(realm(), *this));

Libraries/LibWeb/WebGL/WebGL2RenderingContext.h

@@ -86,6 +86,7 @@ private:
     GC::Ptr<Extensions::EXTRenderSnorm> m_ext_render_snorm;
     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;
 
     virtual void set_error(GLenum error) override;
 };

Libraries/LibWeb/WebGL/WebGLRenderingContext.cpp

@@ -18,6 +18,7 @@
 #include <LibWeb/WebGL/Extensions/EXTBlendMinMax.h>
 #include <LibWeb/WebGL/Extensions/OESVertexArrayObject.h>
 #include <LibWeb/WebGL/Extensions/WebGLCompressedTextureS3tc.h>
+#include <LibWeb/WebGL/Extensions/WebGLCompressedTextureS3tcSrgb.h>
 #include <LibWeb/WebGL/Extensions/WebGLDrawBuffers.h>
 #include <LibWeb/WebGL/OpenGLContext.h>
 #include <LibWeb/WebGL/WebGLContextEvent.h>
@@ -97,6 +98,7 @@ void WebGLRenderingContext::visit_edges(Cell::Visitor& visitor)
     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_compressed_texture_s3tc_srgb_extension);
     visitor.visit(m_webgl_draw_buffers_extension);
 }
 
@@ -222,6 +224,15 @@ JS::Object* WebGLRenderingContext::get_extension(String const& name)
         return m_webgl_compressed_texture_s3tc_extension;
     }
 
+    if (name.equals_ignoring_ascii_case("WEBGL_compressed_texture_s3tc_srgb"sv)) {
+        if (!m_webgl_compressed_texture_s3tc_srgb_extension) {
+            m_webgl_compressed_texture_s3tc_srgb_extension = MUST(Extensions::WebGLCompressedTextureS3tcSrgb::create(realm(), this));
+        }
+
+        VERIFY(m_webgl_compressed_texture_s3tc_srgb_extension);
+        return m_webgl_compressed_texture_s3tc_srgb_extension;
+    }
+
     if (name.equals_ignoring_ascii_case("WEBGL_draw_buffers"sv)) {
         if (!m_webgl_draw_buffers_extension) {
             m_webgl_draw_buffers_extension = MUST(Extensions::WebGLDrawBuffers::create(realm(), *this));

Libraries/LibWeb/WebGL/WebGLRenderingContext.h

@@ -85,6 +85,7 @@ private:
     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::WebGLCompressedTextureS3tcSrgb> m_webgl_compressed_texture_s3tc_srgb_extension;
     GC::Ptr<Extensions::WebGLDrawBuffers> m_webgl_draw_buffers_extension;
 
     virtual void set_error(GLenum error) override;

Libraries/LibWeb/idl_files.cmake

@@ -475,6 +475,7 @@ libweb_js_bindings(WebGL/Extensions/EXTRenderSnorm)
 libweb_js_bindings(WebGL/Extensions/EXTTextureNorm16)
 libweb_js_bindings(WebGL/Extensions/OESVertexArrayObject)
 libweb_js_bindings(WebGL/Extensions/WebGLCompressedTextureS3tc)
+libweb_js_bindings(WebGL/Extensions/WebGLCompressedTextureS3tcSrgb)
 libweb_js_bindings(WebGL/Extensions/WebGLDrawBuffers)
 libweb_js_bindings(WebGL/Extensions/WebGLVertexArrayObjectOES)
 libweb_js_bindings(WebGL/WebGL2RenderingContext)