Bringup sample #3 - descriptors

copy.comp

#version 460

layout(local_size_x = 16) in;

layout(set = 0, binding = 0) writeonly buffer Output
{
        uint data[];
} o;

layout(set = 0, binding = 1) uniform usamplerBuffer i;

void main()
{
        o.data[gl_GlobalInvocationID.x] = texelFetch(i, int(gl_GlobalInvocationID.x)).x;
}

test.cpp

#include "device.hpp"
#include "context.hpp"
#include "logging.hpp"
#include <stdlib.h>

static const uint32_t copy_shader[] =
#include "copy.h"
;

static void run_some_code(Vulkan::Device &dev)
{
	Vulkan::BufferCreateInfo info = {};
	info.size = 64;

	info.domain = Vulkan::BufferDomain::Device;
	info.usage = VK_BUFFER_USAGE_STORAGE_BUFFER_BIT;
	info.misc = Vulkan::BUFFER_MISC_ZERO_INITIALIZE_BIT;

	auto gpu_buffer = dev.create_buffer(info);
	dev.set_name(*gpu_buffer, "gpu-buffer");

	info.domain = Vulkan::BufferDomain::Host;
	info.misc = 0;
	info.usage = VK_BUFFER_USAGE_UNIFORM_TEXEL_BUFFER_BIT;

	uint8_t initial_data[16];
	for (uint8_t i = 0; i < 16; i++)
		initial_data[i] = i;
	info.size = sizeof(initial_data);

	auto cpu_buffer = dev.create_buffer(info, initial_data);
	dev.set_name(*cpu_buffer, "cpu-buffer");

	Vulkan::Program *prog = dev.request_program(copy_shader, sizeof(copy_shader));

  // A buffer view is typed. The shader doesn't have to know that it's reading this format.
  // This is a very powerful feature of GPUs.
	Vulkan::BufferViewCreateInfo buffer_view_info = {};
	buffer_view_info.buffer = cpu_buffer.get();
	buffer_view_info.format = VK_FORMAT_R8_UINT;
	buffer_view_info.offset = 0;
	buffer_view_info.range = sizeof(initial_data);
	Vulkan::BufferViewHandle buffer_view = dev.create_buffer_view(buffer_view_info);

	Vulkan::CommandBufferHandle cmd = dev.request_command_buffer(Vulkan::CommandBuffer::Type::Generic);
	cmd->set_program(prog);
  // set and binding will be explained later.
	cmd->set_storage_buffer(/* set */ 0, /* binding */ 0, *gpu_buffer);
	cmd->set_buffer_view(/* set */ 0, /* binding */ 1, *buffer_view);
	cmd->dispatch(1, 1, 1);

	dev.submit(cmd);

	dev.next_frame_context();
}

int main()
{
	if (!Vulkan::Context::init_loader(nullptr))
		return EXIT_FAILURE;

	Vulkan::Context ctx;
	if (!ctx.init_instance_and_device(nullptr, 0, nullptr, 0, Vulkan::CONTEXT_CREATION_ENABLE_ROBUSTNESS_2_BIT))
		return EXIT_FAILURE;

	Vulkan::Device dev;
	dev.set_context(ctx);

	bool has_rdoc = Vulkan::Device::init_renderdoc_capture();

	if (has_rdoc)
		dev.begin_renderdoc_capture();

	run_some_code(dev);

	if (has_rdoc)
		dev.end_renderdoc_capture();
}