OpenGL shaders are not associated with a shader program

Question

I am trying to add shaders with GLFW / GLEW.

I get an error that the shaders are loaded, but they do not have a valid object code.

This is the code for loading shaders:

class SHADER { public: void LoadShaders(const char *vertexFile, const char *fragmentFile); char *vertexShader; char *fragmentShader; private: int Load(const char *filename, char*&shaderSource); fstream file; }; int SHADER::Load(const char *filename, char *&shaderSource) { file.open(filename, ios::in); if(file.is_open()) { file.tellg(); file.seekg(0,ios::end); unsigned long len = file.tellg(); file.seekg(ios::beg); if(len == 0 ) { return -2; } else { shaderSource = new char[len + 1]; file.read(shaderSource,len); file.close(); printf("%s\n",shaderSource); } } else { return -1; } return 0; } void SHADER::LoadShaders(const char *vertexFile, const char *fragmentFile) { int resultVertex = this->Load(vertexFile, vertexShader); int resultFragment = this->Load(fragmentFile, fragmentShader); if(resultVertex ==0 && resultFragment ==0) { printf("Shaders loaded succesfully.\n"); } if(resultVertex == -2) { printf("VertexShader is empty!\n"); } if(resultFragment == -2) { printf("FragmentShader is empty!\n"); } if(resultVertex == -1) { printf("Unable to load VertexShader!\n"); } if(resultFragment == -1) { printf("Unable to load FragmentShader!\n"); } } 

This is the code to initialize the shaders:

 SHADER Shaders; GLhandleARB vertexShader, fragmentShader, shaderProgram; Shaders.LoadShaders("vertexShader.vert","fragmentShader.frag"); const char* vertTemp = Shaders.vertexShader; vertexShader = glCreateShaderObjectARB(GL_VERTEX_SHADER_ARB); glShaderSourceARB(vertexShader, 1, &vertTemp, NULL); glCompileShaderARB(vertexShader); traceShaderInfoLog(vertexShader); const char* fragTemp = Shaders.fragmentShader; fragmentShader = glCreateShaderObjectARB(GL_FRAGMENT_SHADER_ARB); glShaderSourceARB(fragmentShader, 1, &fragTemp, NULL); glCompileShaderARB(fragmentShader); traceShaderInfoLog(fragmentShader); delete[] Shaders.vertexShader; delete[] Shaders.fragmentShader; shaderProgram = glCreateProgramObjectARB(); glAttachObjectARB(shaderProgram,vertexShader); glAttachObjectARB(shaderProgram,fragmentShader); glLinkProgramARB(shaderProgram); traceProgramInfoLog(shaderProgram); glUseProgramObjectARB(shaderProgram); 

These are vertexShader.vert and fragmentShader.frag:

 void main(){ gl_Position = ftransform(); } void main(){ gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0); } 

And this is the error I get when I print the log, I get this really strange character at the end of the scripts, which every time I compile a different character:

 void main(){ //gl_Position = gl_ModelViewProjectionMatrix * gl_Vertex; gl_Position = ftransform(); }┘ void main(){ gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0); }♣ Shaders loaded succesfully. Vertex shader was successfully compiled to run on hardware. Fragment shader failed to compile with the following errors: ERROR: 0:3: error(#132) Syntax error: '<' parse error ERROR: error(#273) 1 compilation errors. No code generated Fragment shader(s) were not successfully compiled before glLinkProgram() was called. Link failed. 

Answer 1

Your download function is most likely the problem: the signature must read

 int SHADER::Load(const char *filename, char *&shaderSource) // Note the & 

for quick fix. You allocate memory in this function and reassign the pointer - you load the source only at this address, but never leave this function.

The compiler most likely receives an empty string due to the fact that the memory is initialized to zero (do you do this when debugging?) And does not interrupt, because sometimes it is normal. But the linker notices that there really is no code for the link!

Answer 2

When it does not bind, retrieve the link error log, which may have additional hints.

See glGetProgramInfoLog .