Bug Description

When running WebGL2 content or conformance tests in JSAR Runtime, the following error is triggered on code that calls:

gl.getInternalformatParameter(target, internalformat, pname);

Error:

Uncaught TypeError: gl.getInternalformatParameter is not a function

Spec Reference

• WebGL 2.0 Spec §5.19.6 getInternalformatParameter
• MDN
• Chromium Implementation

Expected Behavior

gl.getInternalformatParameter() should be implemented and return correct internal format parameters.

• Typical usage: querying support for texture formats, sample counts, etc.

Root Cause

• JSAR does not currently implement the getInternalformatParameter function on the WebGL2RenderingContext binding.
• Calls to this function yield a TypeError in JavaScript, breaking WebGL2 applications and test suites.

Acceptance Criteria

• gl.getInternalformatParameter must be present and callable on all WebGL2 contexts.
• The function should return correct values for supported targets/internalformats/pnames
• Conformance test files calling this function pass

Implementation Guidance (C++)

Implement the binding for getInternalformatParameter:

JSValue WebGL2RenderingContext::getInternalformatParameter(GLenum target, GLenum internalformat, GLenum pname) {
    // Query underlying GL implementation
    GLint params[16] = {0};
    GLint numParams = 0;
    glGetInternalformativ(target, internalformat, pname, 16, params, &numParams);
    // Return as JS array or value as per WebGL2 spec
    // See Chromium/WebKit/Gecko implementations for details
}

• See Chromium/WebKit code for native logic and error handling.
• Update JS bindings so this function is exposed and documented as per spec.

Impact

• Required for compatibility with WebGL2 applications, including Three.js/Babylon.js advanced rendering and all Khronos conformance tests.

Please prioritize as this blocks WebGL2 conformance and ecosystem compatibility.