I'm trying to figure out what the best way is to generate an OpenGL texture using a compute shader. So far, I've read that pixel buffer objects are good for non-blocking CPU -> GPU transfers, and that compute shaders are capable of reading and writing buffers regardless of how they're bound. Ideally, I'd like to avoid as many copies as possible. In other words, I'd like to allocate a buffer on the GPU, write compressed texture data to it, and then use that buffer as a texture object in a shader.
Currently, my code looks something like this:
GLuint buffer; glGenBuffers(1, &buffer); glBindBuffer(GL_SHADER_STORAGE_BUFFER, buffer); glBufferStorage(GL_SHADER_STORAGE_BUFFER, tex_size_in_bytes, 0, 0); glBindBuffer(GL_SHADER_STORAGE_BUFFER, 0); // Bind buffer to resource in compute shader // execute compute shader glBindBuffer(GL_PIXEL_UNPACK_BUFFER, buffer); glCompressedTexImage2D(GL_TEXTURE_2D, 0, fmt, w, h, 0, tex_size_in_bytes, 0);
Is this correct? I read somewhere about guaranteeing synchronization, too. What do I need to add to make sure that my compute shader completes execution prior to copying from the buffer object?