opengl - GLSL 4.2 - 语法错误：“布局”解析错误

Question

所以，我最近发现了一个有趣的着色器并尝试编译它。

但是，GLSL 编译器抛出了以下错误：

ERROR: 0:50: error(#132) Syntax error: "layout" parse error

@（片段着色器）

#version 420

...

uint ImageAtomic_Average_RGBA8(layout (r32ui) volatile uimage3D Img, ivec3 Coords, vec4 NewVal)
{ ... }

细节：

• 显卡：AMD Radeon HD 7870（支持OpenGL 4.20）
• 我尝试了 4.2 驱动程序和 4.3 beta 驱动程序。

Answer 1

A layout qualifier cannot be part of the function's signature. Section 6.1.1 of the GLSL 4.40 Specification defines the following grammar for a function prototype:

function-prototype :
precision-qualifier type function-name(*parameter-qualifiers* precision-qualifier type name array-specifier, ... )

Now, a parameter-qualifier can be one of

const
in
out
inout
precise
memory qualifier (volatile, ...)
precision qualifier(lowp, ...)

Consistently, section 4.10 explicitly states:

Layout qualifiers cannot be used on formal function parameters [..]

If you drop the layout qualifier, you should be fine. If not, it's a driver bug.