Problem

Calling context.getParameter() for several numeric or stateful parameters (not direct object bindings) such as:

• FRAGMENT_SHADER_DERIVATIVE_HINT
• PACK_ROW_LENGTH
• PACK_SKIP_PIXELS
• PACK_SKIP_ROWS
• UNPACK_IMAGE_HEIGHT
• UNPACK_ROW_LENGTH
• UNPACK_SKIP_IMAGES
• UNPACK_SKIP_PIXELS
• UNPACK_SKIP_ROWS
• RASTERIZER_DISCARD
• SAMPLE_ALPHA_TO_COVERAGE
• SAMPLE_COVERAGE
• READ_BUFFER
• DRAW_BUFFER0
• MAX_3D_TEXTURE_SIZE
• MAX_SERVER_WAIT_TIMEOUT
• MIN_PROGRAM_TEXEL_OFFSET
• UNIFORM_BUFFER_OFFSET_ALIGNMENT

...returns undefined instead of a valid value (should be integer, float, or boolean according to spec). Some should have a default value (e.g., 0 for PACK_ROW_LENGTH), or a specific constant (e.g., 1029 for DRAW_BUFFER0).

Expected Behavior

All WebGL2 state and capability parameters queried via getParameter() should always return a correct spec-compliant value, never undefined. This applies to API conformance and ensures portability.

Impact

• Causes conformance tests to fail
• Prevents expected application logic (e.g., typed array allocations, feature detection)

References

• WebGL2 getParameter Spec
• Chromium implementation example

Suggested Actions

• Audit numeric/boolean parameters in WebGL2 context.getParameter()
• Implement default/fallback values according to specification
• Add/extend regression tests to cover these cases

Category: WebGL2 parameter state compliance