Method prepare_offscreen_buffer

samples/api/hpp_hdr/hpp_hdr.cpp:590–635

Prepare a new framebuffer and attachments for offscreen rendering (G-Buffer)

// Prepare a new framebuffer and attachments for offscreen rendering (G-Buffer)
void HPPHDR::prepare_offscreen_buffer()
{
	// We need to select a format that supports the color attachment blending flag, so we iterate over multiple formats to find one that supports this flag
	const std::vector<vk::Format> float_format_priority_list = {
	    vk::Format::eR32G32B32A32Sfloat,
	    vk::Format::eR16G16B16A16Sfloat        // Guaranteed blend support for this
	};

	vk::Format color_format = vkb::common::choose_blendable_format(get_device().get_gpu().get_handle(), float_format_priority_list);

	{
		offscreen.extent = extent;

		// Color attachments

		// We are using two 128-Bit RGBA floating point color buffers for this sample
		// In a performance or bandwidth-limited scenario you should consider using a format with lower precision
		offscreen.color[0] = create_attachment(color_format, vk::ImageUsageFlagBits::eColorAttachment);
		offscreen.color[1] = create_attachment(color_format, vk::ImageUsageFlagBits::eColorAttachment);
		// Depth attachment
		offscreen.depth = create_attachment(depth_format, vk::ImageUsageFlagBits::eDepthStencilAttachment);

		offscreen.render_pass = create_offscreen_render_pass();

		offscreen.framebuffer = vkb::common::create_framebuffer(
		    get_device().get_handle(), offscreen.render_pass, {offscreen.color[0].view, offscreen.color[1].view, offscreen.depth.view}, offscreen.extent);

		// Create sampler to sample from the color attachments
		offscreen.sampler = vkb::common::create_sampler(get_device().get_gpu().get_handle(), get_device().get_handle(), color_format,
		                                                vk::Filter::eNearest, vk::SamplerAddressMode::eClampToEdge, 1.0f, 1.0f);
	}

	// Bloom separable filter pass
	{
		filter_pass.extent = extent;

		// Color attachments

		// Floating point color attachment
		filter_pass.color       = create_attachment(color_format, vk::ImageUsageFlagBits::eColorAttachment);
		filter_pass.render_pass = create_filter_render_pass();
		filter_pass.framebuffer = vkb::common::create_framebuffer(get_device().get_handle(), filter_pass.render_pass, {filter_pass.color.view}, filter_pass.extent);
		filter_pass.sampler     = vkb::common::create_sampler(get_device().get_gpu().get_handle(), get_device().get_handle(),
		                                                      color_format, vk::Filter::eNearest, vk::SamplerAddressMode::eClampToEdge, 1.0f, 1.0f);
	}
}

// Prepare and initialize uniform buffer containing shader uniforms
void HPPHDR::prepare_uniform_buffers()