Method render

samples/extensions/open_gl_interop/open_gl_interop.cpp:616–670

}

void OpenGLInterop::render(float)
{
	if (!prepared)
	{
		return;
	}

	ApiVulkanSample::prepare_frame();
	// RENDER
	float time = static_cast<float>(timer.elapsed());
	// The GL shader animates the image, so provide the time as input
	glProgramUniform1f(gl_data->program, 1, time);

	// Wait (on the GPU side) for the Vulkan semaphore to be signaled
	GLenum srcLayout = GL_LAYOUT_COLOR_ATTACHMENT_EXT;
	glWaitSemaphoreEXT(gl_data->gl_ready, 0, nullptr, 1, &gl_data->color, &srcLayout);

	// Draw to the framebuffer
	glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);

	// Once drawing is complete, signal the Vulkan semaphore indicating
	// it can continue with it's render
	GLenum dstLayout = GL_LAYOUT_SHADER_READ_ONLY_EXT;
	glSignalSemaphoreEXT(gl_data->gl_complete, 0, nullptr, 1, &gl_data->color, &dstLayout);

	// When using synchronization across multiple GL context, or in this case
	// across OpenGL and another API, it's critical that an operation on a
	// synchronization object that will be waited on in another context or API
	// is flushed to the GL server.
	//
	// Failure to flush the operation can cause the GL driver to sit and wait for
	// sufficient additional commands in the buffer before it flushes automatically
	// but depending on how the waits and signals are structured, this may never
	// occur.
	glFlush();
	// RENDER

	std::array<VkPipelineStageFlags, 2> waitStages{{VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT, VK_PIPELINE_STAGE_FRAGMENT_SHADER_BIT}};
	std::array<VkSemaphore, 2>          waitSemaphores{{semaphores.acquired_image_ready, sharedSemaphores.gl_complete}};

	std::array<VkSemaphore, 2> signalSemaphores{{semaphores.render_complete, sharedSemaphores.gl_ready}};
	// Command buffer to be submitted to the queue
	submit_info.waitSemaphoreCount   = vkb::to_u32(waitSemaphores.size());
	submit_info.pWaitSemaphores      = waitSemaphores.data();
	submit_info.pWaitDstStageMask    = waitStages.data();
	submit_info.signalSemaphoreCount = vkb::to_u32(signalSemaphores.size());
	submit_info.pSignalSemaphores    = signalSemaphores.data();
	submit_info.commandBufferCount   = 1;
	submit_info.pCommandBuffers      = &draw_cmd_buffers[current_buffer];

	// Submit to queue
	VK_CHECK(vkQueueSubmit(queue, 1, &submit_info, VK_NULL_HANDLE));

	ApiVulkanSample::submit_frame();
}

void OpenGLInterop::view_changed()
{