glsl着色器在运行时的编译问题 [英] glsl shader compilation issue at runtime

问题描述

我正在开发一个使用OpenGL 4.0着色器的项目.

I'm working on a project that uses OpenGL 4.0 shaders.

我必须提供对 glShaderSource()的调用带有一个char数组的数组，该数组代表着色器的源.

I have to supply the call to glShaderSource() with an array of char arrays, which represents the source of the shader.

着色器编译失败，出现以下错误:

The shader compilation is failing, with the following errors:

(0) : error C0206: invalid token "<null atom>" in version line
(0) : error C0000: syntax error, unexpected $end at token "<EOF>"

这是我的(hello world)着色器-直接来自OpenGL 4.0着色语言食谱

Here's my (hello world) shader - straight from OpenGL 4.0 shading language cookbook

#version 400

in  vec3        VertexPosition;
in  vec3        VertexColor;
out vec3        Color;

void main()
{
    Color       = VertexColor;
    gl_Position = vec4( VertexColor, 1.0 );
}

这是我的代码，用于将着色器文件读入C ++代码，并在运行时编译着色器:

And here's my code to read the shader file into my C++ code, and compile the shader at runtime:

const int       nMaxLineSize    = 1024;
char            sLineBuffer[nMaxLineSize];
ifstream        stream;
vector<string>  vsLines;
GLchar**        ppSrc;
GLint*          pnSrcLineLen;
int             nNumLines;


stream.open( m_sShaderFile.c_str(), std::ios::in );

while( (stream.good()) && (stream.getline(sLineBuffer, nMaxLineSize)) )
{
    if( strlen(sLineBuffer) > 0 )
        vsLines.push_back( string(sLineBuffer) );
}

stream.close();


nNumLines       = vsLines.size();
pnSrcLineLen    = new GLint[nNumLines];
ppSrc           = new GLchar*[nNumLines];

for( int n = 0; n < nNumLines; n ++ )
{
    string &    sLine       = vsLines.at(n);
    int         nLineLen    = sLine.length();
    char *      pNext       = new char[nLineLen+1];

    memcpy( (void*)pNext, sLine.c_str(), nLineLen );                
    pNext[nLineLen] = '\0'; 

    ppSrc[n]        = pNext;
    pnSrcLineLen[n] = nLineLen+1;
}
vsLines.clear();

// just for debugging purposes (lines print out just fine..)
for( int n = 0; n < nNumLines; n ++ )           
    ATLTRACE( "line %d: %s\r\n", n, ppSrc[n] );

// Create the shader
m_nShaderId = glCreateShader( m_nShaderType );

// Compile the shader
glShaderSource( m_nShaderId, nNumLines, (const GLchar**)ppSrc, (GLint*) pnSrcLineLen );
glCompileShader( m_nShaderId );

// Determine compile status
GLint nResult = GL_FALSE;
glGetShaderiv( m_nShaderId, GL_COMPILE_STATUS, &nResult );

C ++代码按预期执行，但是着色器编译失败.谁能发现我可能做错了什么?

The C++ code executes as expected, but the shader compilation fails. Can anyone spot what I might be doing wrong?

我感觉这可能与行尾字符有关，但是由于这是我第一次进行着色器编译，所以我被卡住了！

I have a feeling that this may be to do with end of line characters somehow, but as this is my first attempt at shader compilation, I'm stuck!

我已经阅读了有关着色器编译的其他SO答案，但是它们似乎特定于Java/其他语言，而不是C ++.如果有帮助，我就在win32平台上.

I've read other SO answers on shader compilation, but they seem specific to Java / other languages, not C++. If it helps, I'm on the win32 platform.

推荐答案

只是预感:

您是否尝试使用长度参数NULL调用glShaderSource?在这种情况下，OpenGL将假定您的代码以null结尾.

Have you tried calling glShaderSource with NULL as length parameter? In that case OpenGL will assume your code to be null-terminated.

(由于愚蠢而编辑)

这篇关于glsl着色器在运行时的编译问题的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！