shader: remove second IR layer

src/graphics/shader/shaderPixelParameter.cpp

@@ -0,0 +1,48 @@
+#include "graphics/shader/shader.h"
+
+#include "common/assert.h"
+
+namespace Libs::Graphics {
+
+namespace {
+
+constexpr uint32_t PsInputOffsetMask = 0x0000001fu;
+constexpr uint32_t PsInputFlatShade  = 0x00000400u;
+
+} // namespace
+
+uint32_t ShaderPixelParameterMappedLocation(const ShaderPixelInputInfo& info, uint32_t input) {
+	return input < info.input_num ? info.interpolator_settings[input] & PsInputOffsetMask : input;
+}
+
+uint32_t ShaderPixelParameterLocation(const ShaderPixelInputInfo& info,
+                                      std::span<const uint32_t> active_inputs, uint32_t input) {
+	std::array<bool, 32> used_locations {};
+	for (const auto active_input: active_inputs) {
+		auto location = ShaderPixelParameterMappedLocation(info, active_input);
+		if (location < used_locations.size() && used_locations[location]) {
+			location = active_input;
+			while (location < used_locations.size() && used_locations[location]) {
+				location++;
+			}
+			EXIT_NOT_IMPLEMENTED(location >= used_locations.size());
+		}
+
+		if (active_input == input) {
+			return location;
+		}
+		used_locations[location] = true;
+	}
+	return ShaderPixelParameterMappedLocation(info, input);
+}
+
+bool ShaderPixelParameterIsFlat(const ShaderPixelInputInfo& info, uint32_t input) {
+	return input < info.input_num && (info.interpolator_settings[input] & PsInputFlatShade) != 0 &&
+	       !ShaderPixelParameterIsCustom(info, input);
+}
+
+bool ShaderPixelParameterIsCustom(const ShaderPixelInputInfo& info, uint32_t input) {
+	return input < 32u && (info.custom_interpolation_mask & (1u << input)) != 0;
+}
+
+} // namespace Libs::Graphics