video_core: Add BCn decoding support

externals/CMakeLists.txt

@@ -157,6 +157,9 @@ endif()
 add_library(stb stb/stb_dxt.cpp)
 target_include_directories(stb PUBLIC ./stb)
 
+add_library(bc_decoder bc_decoder/bc_decoder.cpp)
+target_include_directories(bc_decoder PUBLIC ./bc_decoder)
+
 if (ANDROID)
    if (ARCHITECTURE_arm64)
        add_subdirectory(libadrenotools)

externals/bc_decoder/bc_decoder.h

@@ -0,0 +1,43 @@
+// SPDX-License-Identifier: MPL-2.0
+// Copyright © 2022 Skyline Team and Contributors (https://github.com/skyline-emu/)
+
+#pragma once
+
+#include <cstdint>
+
+namespace bcn {
+    /**
+     * @brief Decodes a BC1 encoded image to R8G8B8A8
+     */
+    void DecodeBc1(const uint8_t *src, uint8_t *dst, size_t x, size_t y, size_t width, size_t height);
+
+    /**
+     * @brief Decodes a BC2 encoded image to R8G8B8A8
+     */
+    void DecodeBc2(const uint8_t *src, uint8_t *dst, size_t x, size_t y, size_t width, size_t height);
+
+    /**
+     * @brief Decodes a BC3 encoded image to R8G8B8A8
+     */
+    void DecodeBc3(const uint8_t *src, uint8_t *dst, size_t x, size_t y, size_t width, size_t height);
+
+    /**
+     * @brief Decodes a BC4 encoded image to R8
+     */
+    void DecodeBc4(const uint8_t *src, uint8_t *dst, size_t x, size_t y, size_t width, size_t height, bool isSigned);
+
+    /**
+     * @brief Decodes a BC5 encoded image to R8G8
+     */
+    void DecodeBc5(const uint8_t *src, uint8_t *dst, size_t x, size_t y, size_t width, size_t height, bool isSigned);
+
+    /**
+     * @brief Decodes a BC6 encoded image to R16G16B16A16
+     */
+    void DecodeBc6(const uint8_t *src, uint8_t *dst, size_t x, size_t y, size_t width, size_t height, bool isSigned);
+
+    /**
+     * @brief Decodes a BC7 encoded image to R8G8B8A8
+     */
+    void DecodeBc7(const uint8_t *src, uint8_t *dst, size_t x, size_t y, size_t width, size_t height);
+}