PEN_2_4

Function to read shader source code from a file:

std::string readShaderSource(const char *filePath); This function reads the content of the file specified by filePath and returns the shader source code as a string.

• Parameters:

• filePath: A character string representing the path to the file containing the shader source code.

• Return:

Returns a std::string containing the shader source code.

• Detailed description:

• First, an empty string content is initialized to store the file content.

• The file is opened using std::ifstream in input mode (std::ios::in).

• If the file cannot be opened, an error message is printed and an empty string is returned.

• The file is read line by line using getline and the content is accumulated in the content string, adding a newline at the end of each line.

• Finally, the file is closed and the read content is returned.

Function to create a shader program:

GLuint createShaderProgram(); This function creates a shader program, compiling and linking a vertex shader and a fragment shader, and returns the program identifier.

• Return:

Returns a GLuint which is the identifier of the created shader program.

• Detailed description:

• The source codes of the vertex and fragment shaders are read from the files ./vertex_shader4.glsl and ./fragment_shader4.glsl using the readShaderSource function.

• The character strings (const char*) are obtained from the read contents.

• Vertex and fragment shaders are created using glCreateShader.

• The shader source code is set using glShaderSource.

• Shaders are compiled using glCompileShader.

• If there were compilation errors, the error logs are printed using checkOpenGLError and printShaderLog.

• A shader program is created using glCreateProgram.

• The shaders are attached to the program using glAttachShader.

• The program is linked using glLinkProgram.

• If there were linking errors, the error logs are printed using checkOpenGLError and printShaderLog.

• Finally, the shader program identifier is returned.