OpenGL 片段着色器未在 Intel HD 4000 图形上编译答案

【问题标题】：OpenGL Fragment Shader not compiling on Intel HD 4000 graphicsOpenGL 片段着色器未在 Intel HD 4000 图形上编译
【发布时间】：2020-06-05 11:06:27
【问题描述】：

这个着色器似乎在我的 ryzen 3 2200g 上的 Vega 8 iGPU 上编译得很好，但相同的片段着色器不能在 intel hd 4000 图形上编译。真的有着色器错误还是我做错了什么？我还采取措施不使用int 引用制服。请帮忙。

#version 330 core
in vec2 TexCoord;

// I am using a batch rendering method. The "TexElement" is the slot to which the texture is bound to
in flat int TexElement;

// Color to multiply with the texture color also called tint
in flat vec4 MultiplyColor;

// Outputted color
out vec4 color;

uniform sampler2D u_Textures[32];

void main()
{
    switch (TexElement)
    {
        case 0 : color = texture(u_Textures[0], TexCoord) * MultiplyColor; break;
        case 1 : color = texture(u_Textures[1], TexCoord) * MultiplyColor; break;
        case 2 : color = texture(u_Textures[2], TexCoord) * MultiplyColor; break;
        case 3 : color = texture(u_Textures[3], TexCoord) * MultiplyColor; break;
        case 4 : color = texture(u_Textures[4], TexCoord) * MultiplyColor; break;
        case 5 : color = texture(u_Textures[5], TexCoord) * MultiplyColor; break;
        case 6 : color = texture(u_Textures[6], TexCoord) * MultiplyColor; break;
        case 7 : color = texture(u_Textures[7], TexCoord) * MultiplyColor; break;
        case 8 : color = texture(u_Textures[8], TexCoord) * MultiplyColor; break;
        case 9 : color = texture(u_Textures[9], TexCoord) * MultiplyColor; break;
        case 10 : color = texture(u_Textures[10], TexCoord) * MultiplyColor; break;
        case 11 : color = texture(u_Textures[11], TexCoord) * MultiplyColor; break;
        case 12 : color = texture(u_Textures[12], TexCoord) * MultiplyColor; break;
        case 13 : color = texture(u_Textures[13], TexCoord) * MultiplyColor; break;
        case 14 : color = texture(u_Textures[14], TexCoord) * MultiplyColor; break;
        case 15 : color = texture(u_Textures[15], TexCoord) * MultiplyColor; break;
        case 16 : color = texture(u_Textures[16], TexCoord) * MultiplyColor; break;
        case 17 : color = texture(u_Textures[17], TexCoord) * MultiplyColor; break;
        case 18 : color = texture(u_Textures[18], TexCoord) * MultiplyColor; break;
        case 19 : color = texture(u_Textures[19], TexCoord) * MultiplyColor; break;
        case 20 : color = texture(u_Textures[20], TexCoord) * MultiplyColor; break;
        case 21 : color = texture(u_Textures[21], TexCoord) * MultiplyColor; break;
        case 22 : color = texture(u_Textures[22], TexCoord) * MultiplyColor; break;
        case 23 : color = texture(u_Textures[23], TexCoord) * MultiplyColor; break;
        case 24 : color = texture(u_Textures[24], TexCoord) * MultiplyColor; break;
        case 25 : color = texture(u_Textures[25], TexCoord) * MultiplyColor; break;
        case 26 : color = texture(u_Textures[26], TexCoord) * MultiplyColor; break;
        case 27 : color = texture(u_Textures[27], TexCoord) * MultiplyColor; break;
        case 28 : color = texture(u_Textures[28], TexCoord) * MultiplyColor; break;
        case 29 : color = texture(u_Textures[29], TexCoord) * MultiplyColor; break;
        case 30 : color = texture(u_Textures[30], TexCoord) * MultiplyColor; break;
        case 31 : color = texture(u_Textures[31], TexCoord) * MultiplyColor; break;
        default : color = MultiplyColor; break;
    }
}

这里是 glInfoLog ：

ERROR: 0:19: 'u_Textures' : undeclared identifier 
ERROR: 0:19: 'u_Textures' :  left of '[' is not of type array, matrix, or vector  
ERROR: 0:19: 'texture' : no matching overloaded function found (using implicit conversion) 
ERROR: 0:20: 'u_Textures' :  left of '[' is not of type array, matrix, or vector  
ERROR: 0:20: 'texture' : no matching overloaded function found (using implicit conversion) 
ERROR: 0:21: 'u_Textures' :  left of '[' is not of type array, matrix, o

我还验证了传递给 GLSL 编译器的实际字符串，但没有区别。

我真的不确定问题是什么。

【问题讨论】：

glGetIntegerv(GL_MAX_TEXTURE_IMAGE_UNITS, ...) 的值是多少？您似乎试图通过将它们打包在 switch 语句中来规避着色器数组索引必须是常量表达式的限制。我不确定这（通常）是否有效）。你肯定没有有效的衍生品。如果我是你，我会使用一个 3D 纹理或数组纹理。
This 主题可能是相关的。可能您没有支持此 GLSL 版本的驱动程序，或者此 GPU 根本不支持此版本
Intel HD Graphics 4000 支持 opengl 直到 4.0。这里是编译问题。我遵循 BDL 的意见。

标签： c++ opengl glsl shader

【解决方案1】：

Intel HD 4000 显卡最多仅支持 16 个纹理插槽或单元。您正在接收大小为 32 的 sampler2D 数组。大于 16。如果您将数组大小更改为 16 并注释掉额外的情况，它将起作用。这是更新后的着色器代码：

#version 330 core
in vec2 TexCoord;

// I am using a batch rendering method. The "TexElement" is the slot to which the texture is bound to
in flat int TexElement;

// Color to multiply with the texture color also called tint
in flat vec4 MultiplyColor;

// Outputted color
out vec4 color;

uniform sampler2D u_Textures[16];

void main()
{
    switch (TexElement)
    {
        case 0 : color = texture(u_Textures[0], TexCoord) * MultiplyColor; break;
        case 1 : color = texture(u_Textures[1], TexCoord) * MultiplyColor; break;
        case 2 : color = texture(u_Textures[2], TexCoord) * MultiplyColor; break;
        case 3 : color = texture(u_Textures[3], TexCoord) * MultiplyColor; break;
        case 4 : color = texture(u_Textures[4], TexCoord) * MultiplyColor; break;
        case 5 : color = texture(u_Textures[5], TexCoord) * MultiplyColor; break;
        case 6 : color = texture(u_Textures[6], TexCoord) * MultiplyColor; break;
        case 7 : color = texture(u_Textures[7], TexCoord) * MultiplyColor; break;
        case 8 : color = texture(u_Textures[8], TexCoord) * MultiplyColor; break;
        case 9 : color = texture(u_Textures[9], TexCoord) * MultiplyColor; break;
        case 10 : color = texture(u_Textures[10], TexCoord) * MultiplyColor; break;
        case 11 : color = texture(u_Textures[11], TexCoord) * MultiplyColor; break;
        case 12 : color = texture(u_Textures[12], TexCoord) * MultiplyColor; break;
        case 13 : color = texture(u_Textures[13], TexCoord) * MultiplyColor; break;
        case 14 : color = texture(u_Textures[14], TexCoord) * MultiplyColor; break;
        case 15 : color = texture(u_Textures[15], TexCoord) * MultiplyColor; break;
        default : color = MultiplyColor; break;
    }
}

谢谢！

【讨论】：