Method prepare

samples/extensions/open_gl_interop/open_gl_interop.cpp:544–614

}

bool OpenGLInterop::prepare(const vkb::ApplicationOptions &options)
{
	if (!ApiVulkanSample::prepare(options))
	{
		return false;
	}

	// Create off screen context
	gl_context = new OffscreenContext{};
	gl_data    = new GLData{};

	prepare_shared_resources();

	gl_data->program = gl_context->build_program(OPENGL_VERTEX_SHADER, OPENGL_FRAGMENT_SHADER);

	timer.start();

	glDisable(GL_DEPTH_TEST);

	// Create the texture for the FBO color attachment.
	// This only reserves the ID, it doesn't allocate memory
	glGenTextures(1, &gl_data->color);
	glBindTexture(GL_TEXTURE_2D, gl_data->color);

	// Create the GL identifiers

	// semaphores
	glGenSemaphoresEXT(1, &gl_data->gl_ready);
	glGenSemaphoresEXT(1, &gl_data->gl_complete);
	// memory
	glCreateMemoryObjectsEXT(1, &gl_data->mem);

	GLint dedicated = GL_TRUE;
	glMemoryObjectParameterivEXT(gl_data->mem, GL_DEDICATED_MEMORY_OBJECT_EXT, &dedicated);

	// Platform specific import.
	glImportSemaphore(gl_data->gl_ready, GL_HANDLE_TYPE, shareHandles.gl_ready);
	glImportSemaphore(gl_data->gl_complete, GL_HANDLE_TYPE, shareHandles.gl_complete);
	glImportMemory(gl_data->mem, sharedTexture.allocationSize, GL_HANDLE_TYPE, shareHandles.memory);

	// Use the imported memory as backing for the OpenGL texture.  The internalFormat, dimensions
	// and mip count should match the ones used by Vulkan to create the image and determine it's memory
	// allocation.
	glTextureStorageMem2DEXT(gl_data->color, 1, GL_RGBA8, SHARED_TEXTURE_DIMENSION,
	                         SHARED_TEXTURE_DIMENSION, gl_data->mem, 0);
	glBindTexture(GL_TEXTURE_2D, 0);

	// The remaining initialization code is all standard OpenGL
	glGenVertexArrays(1, &gl_data->vao);
	glBindVertexArray(gl_data->vao);

	glGenFramebuffers(1, &gl_data->fbo);
	glBindFramebuffer(GL_FRAMEBUFFER, gl_data->fbo);
	glFramebufferTexture(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, gl_data->color, 0);

	glUseProgram(gl_data->program);
	glProgramUniform3f(gl_data->program, 0, static_cast<float>(SHARED_TEXTURE_DIMENSION),
	                   static_cast<float>(SHARED_TEXTURE_DIMENSION), 0.0f);