WebGL OES_shader_multisample_interpolation Extension Specification

Name

OES_shader_multisample_interpolation

Contact

WebGL working group (public_webgl 'at' khronos.org)

Contributors

Members of the WebGL working group

Version

Last modified date: April 18, 2024
Revision: 2

Number

WebGL extension #57

Dependencies

Written against the WebGL API 2.0 specification.

Overview

This extension exposes the OES_shader_multisample_interpolation functionality to WebGL.

There are no WebGL-specific behavioral changes.

Consult the above extension for documentation, issues and new functions and enumerants.

When this extension is enabled:

• When a shader enables, requires, or warns OES_shader_multisample_interpolation with an #extension directive:
  • genType interpolateAtCentroid(genType interpolant) is a built-in function.
  • genType interpolateAtSample(genType interpolant, int id) is a built-in function.
  • genType interpolateAtOffset(genType interpolant, vec2 offset) is a built-in function.
  • Vertex outputs and fragment inputs may be declared with a sample interpolation qualifier.
• The GLSL macro OES_shader_multisample_interpolation is defined as 1.

IDL

[Exposed=(Window,Worker), LegacyNoInterfaceObject]
interface OES_shader_multisample_interpolation {
    const GLenum MIN_FRAGMENT_INTERPOLATION_OFFSET_OES  = 0x8E5B;
    const GLenum MAX_FRAGMENT_INTERPOLATION_OFFSET_OES  = 0x8E5C;
    const GLenum FRAGMENT_INTERPOLATION_OFFSET_BITS_OES = 0x8E5D;
};
  

New Tokens

any getParameter(GLenum pname)

New enums are accepted as the pname parameter.

The return type of this method depends on the parameter queried:

pname	returned type
MIN_FRAGMENT_INTERPOLATION_OFFSET_OES	GLfloat
MAX_FRAGMENT_INTERPOLATION_OFFSET_OES	GLfloat
FRAGMENT_INTERPOLATION_OFFSET_BITS_OES	GLint

Revision History

Revision 1, 2023/06/01

• Initial Draft.

Revision 2, 2024/04/18

• Promoted to Community Approved.