Method PipelineLayout

framework/core/pipeline_layout.cpp:28–123

namespace vkb
{
PipelineLayout::PipelineLayout(vkb::core::DeviceC &device, const std::vector<ShaderModule *> &shader_modules) :
    device{device},
    shader_modules{shader_modules}
{
	// Collect and combine all the shader resources from each of the shader modules
	// Collate them all into a map that is indexed by the name of the resource
	for (auto *shader_module : shader_modules)
	{
		for (const auto &shader_resource : shader_module->get_resources())
		{
			std::string key = shader_resource.name;

			// Since 'Input' and 'Output' resources can have the same name, we modify the key string
			if (shader_resource.type == ShaderResourceType::Input || shader_resource.type == ShaderResourceType::Output)
			{
				key = std::to_string(shader_resource.stages) + "_" + key;
			}

			auto it = shader_resources.find(key);

			if (it != shader_resources.end())
			{
				// Append stage flags if resource already exists
				it->second.stages |= shader_resource.stages;
			}
			else
			{
				// Create a new entry in the map
				shader_resources.emplace(key, shader_resource);
			}
		}
	}

	// Sift through the map of name indexed shader resources
	// Separate them into their respective sets
	for (auto &it : shader_resources)
	{
		auto &shader_resource = it.second;

		// Find binding by set index in the map.
		auto it2 = shader_sets.find(shader_resource.set);

		if (it2 != shader_sets.end())
		{
			// Add resource to the found set index
			it2->second.push_back(shader_resource);
		}
		else
		{
			// Create a new set index and with the first resource
			shader_sets.emplace(shader_resource.set, std::vector<ShaderResource>{shader_resource});
		}
	}

	// Create a descriptor set layout for each shader set in the shader modules
	for (auto &shader_set_it : shader_sets)
	{
		descriptor_set_layouts.emplace_back(&device.get_resource_cache().request_descriptor_set_layout(shader_set_it.first, shader_modules, shader_set_it.second));