[librptexture] GodotSTEX: Initial implementation of ASTC 8x8 decoding.

Added the ASTC decoder from Basis Universal.

FIXME: The decoded images have swapped R and B channels.

cmake/options.cmake

@@ -87,6 +87,9 @@ OPTION(ENABLE_LIBMSPACK "Enable libmspack-xenia for Xbox 360 executables." ON)
 # Enable the PowerVR Native SDK subset for PVRTC decompression.
 OPTION(ENABLE_PVRTC "Enable the PowerVR Native SDK subset for PVRTC decompression." ON)
 
+# Enable the ASTC decoder from Basis Universal.
+OPTION(ENABLE_ASTC "Enable ASTC decoding using the Basis Universal decoder." ON)
+
 # Enable precompiled headers.
 # FIXME: Not working properly on older gcc. Use cmake-3.16.0's built-in PCH?
 IF(MSVC)

debian/copyright

@@ -159,6 +159,11 @@ Files:
 Copyright: Copyright (C) 1996-2017 Markus Franz Xaver Johannes Oberhumer
 License: GPL-2+
 
+Files:
+ extlib/basisu_astc/*
+Copyright: Copyright 2016 The Android Open Source Project
+License: Apache-2.0
+
 License: BSD-2-clause
  All rights reserved.
  .
@@ -486,3 +491,22 @@ License: TGA-2.0
  here:
  .
  http://googlesites.inequation.org/tgautilities
+
+License: Apache-2.0
+ Licensed to the Apache Software Foundation (ASF) under one or more
+ contributor license agreements.  See the NOTICE file distributed with
+ this work for additional information regarding copyright ownership.
+ The ASF licenses this file to You under the Apache License, Version 2.0
+ (the "License"); you may not use this file except in compliance with
+ the License.  You may obtain a copy of the License at
+ .
+      https://www.apache.org/licenses/LICENSE-2.0
+ .
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+ .
+ On Debian systems, the full text of the Apache Software License version 2 can
+ be found in the file `/usr/share/common-licenses/Apache-2.0'.

extlib/CMakeLists.txt

@@ -343,3 +343,8 @@ IF(BUILD_TESTING)
 		TARGET_COMPILE_DEFINITIONS(gtest_main INTERFACE GTEST_LINKED_AS_SHARED_LIBRARY=1)
 	ENDIF(WIN32)
 ENDIF(BUILD_TESTING)
+
+# Basis Universal ASTC decoder
+IF(ENABLE_ASTC)
+	ADD_SUBDIRECTORY(basisu_astc)
+ENDIF(ENABLE_ASTC)

extlib/basisu_astc/CMakeLists.txt

@@ -0,0 +1,16 @@
+# Basis Universal ASTC decoder
+PROJECT(basisu_astc LANGUAGES CXX)
+
+ADD_LIBRARY(${PROJECT_NAME} STATIC
+	basisu_astc_decomp.cpp
+	basisu_astc_decomp.h
+	)
+TARGET_INCLUDE_DIRECTORIES(${PROJECT_NAME}
+	PUBLIC  $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}>
+	)
+
+# Unix: Add -fpic/-fPIC in order to use this static library in plugins.
+IF(UNIX AND NOT APPLE)
+	SET(CMAKE_C_FLAGS	"${CMAKE_C_FLAGS} -fpic -fPIC")
+	SET(CMAKE_CXX_FLAGS	"${CMAKE_CXX_FLAGS} -fpic -fPIC")
+ENDIF(UNIX AND NOT APPLE)

extlib/basisu_astc/LICENSE

@@ -0,0 +1,201 @@
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+
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extlib/basisu_astc/_MODIFIED_ZLIB.txt

@@ -0,0 +1,10 @@
+These files were originally sourced from Basis Universal v1.15.
+
+The following changes have been made to the original:
+
+- Only the ASTC decoder is included. It has been modified to build without
+  the rest of Basis Universal, e.g. using std::max<> instead of
+  basisu::maximum<>.
+
+To obtain the original Basis Universal v1.15, visit:
+https://github.com/BinomialLLC/basis_universal

extlib/basisu_astc/basisu_astc_decomp.h

@@ -0,0 +1,44 @@
+#ifndef _TCUASTCUTIL_HPP
+#define _TCUASTCUTIL_HPP
+/*-------------------------------------------------------------------------
+ * drawElements Quality Program Tester Core
+ * ----------------------------------------
+ *
+ * Copyright 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ *//*!
+ * \file
+ * \brief ASTC Utilities.
+ *//*--------------------------------------------------------------------*/
+
+// rom-properties: Disabled the basisu.h include.
+//#include "../transcoder/basisu.h" // to pick up the iterator debug level madness
+#include <vector>
+#include <stdint.h>
+
+namespace basisu_astc
+{
+namespace astc
+{
+
+// Unpacks a single ASTC block to pDst
+// If isSRGB is true, the spec requires the decoder to scale the LDR 8-bit endpoints to 16-bit before interpolation slightly differently, 
+// which will lead to different outputs. So be sure to set it correctly (ideally it should match whatever the encoder did).
+bool decompress(uint8_t* pDst, const uint8_t* data, bool isSRGB, int blockWidth, int blockHeight);
+
+} // astc
+} // basisu
+
+#endif

src/librptexture/CMakeLists.txt

@@ -102,8 +102,11 @@ IF(WIN32)
 ENDIF(WIN32)
 
 IF(ENABLE_PVRTC)
-	SET(${PROJECT_NAME}_PVRTC_SRCS decoder/ImageDecoder_PVRTC.cpp)
+	SET(${PROJECT_NAME}_SRCS ${${PROJECT_NAME}_SRCS} decoder/ImageDecoder_PVRTC.cpp)
 ENDIF(ENABLE_PVRTC)
+IF(ENABLE_ASTC)
+	SET(${PROJECT_NAME}_SRCS ${${PROJECT_NAME}_SRCS} decoder/ImageDecoder_ASTC.cpp)
+ENDIF(ENABLE_ASTC)
 
 # CPU-specific and optimized sources.
 IF(CPU_i386 OR CPU_amd64)
@@ -192,7 +195,6 @@ ADD_LIBRARY(${PROJECT_NAME} STATIC
 	${${PROJECT_NAME}_PCH_SRC} ${${PROJECT_NAME}_PCH_H}
 	${${PROJECT_NAME}_SRCS} ${${PROJECT_NAME}_H}
 	${${PROJECT_NAME}_OS_SRCS} ${${PROJECT_NAME}_OS_H}
-	${${PROJECT_NAME}_PVRTC_SRCS}
 	${${PROJECT_NAME}_IFUNC_SRCS}
 	${${PROJECT_NAME}_MMX_SRCS}
 	${${PROJECT_NAME}_SSE2_SRCS}
@@ -243,6 +245,11 @@ IF(ENABLE_PVRTC)
 	TARGET_LINK_LIBRARIES(${PROJECT_NAME} PRIVATE pvrtc)
 ENDIF(ENABLE_PVRTC)
 
+# ASTC decoder from Basis Universal
+IF(ENABLE_ASTC)
+	TARGET_LINK_LIBRARIES(${PROJECT_NAME} PRIVATE basisu_astc)
+ENDIF(ENABLE_ASTC)
+
 # Other libraries.
 IF(WIN32)
 	# libwin32common

src/librptexture/config.librptexture.h.in

@@ -15,4 +15,7 @@
 /* Define to 1 if PVRTC decompression should be enabled. */
 #cmakedefine ENABLE_PVRTC 1
 
+/* Define to 1 if ASTC decompression should be enabled. */
+#cmakedefine ENABLE_ASTC 1
+
 #endif /* __ROMPROPERTIES_LIBRPTEXTURE_CONFIG_H__ */

src/librptexture/decoder/ImageDecoder.hpp

@@ -877,6 +877,23 @@ ATTR_ACCESS_SIZE(read_only, 3, 4)
 rp_image *fromBC7(int width, int height,
 	const uint8_t *img_buf, int img_siz);
 
+#ifdef ENABLE_ASTC
+/**
+ * Convert an ASTC 2D image to rp_image.
+ * @param width Image width
+ * @param height Image height
+ * @param img_buf PVRTC image buffer
+ * @param img_siz Size of image data
+ * @param block_x ASTC block size, X value
+ * @param block_y ASTC block size, Y value
+ * @return rp_image, or nullptr on error.
+ */
+ATTR_ACCESS_SIZE(read_only, 3, 4)
+rp_image *fromASTC(int width, int height,
+	const uint8_t *RESTRICT img_buf, int img_siz,
+	uint8_t block_x, uint8_t block_y);
+#endif /* ENABLE_ASTC */
+
 } }
 
 #endif /* __ROMPROPERTIES_LIBRPTEXTURE_DECODER_IMAGEDECODER_HPP__ */

src/librptexture/decoder/ImageDecoder_ASTC.cpp

@@ -0,0 +1,140 @@
+/***************************************************************************
+ * ROM Properties Page shell extension. (librptexture)                     *
+ * ImageDecoder_ASTC.cpp: Image decoding functions. (ASTC)                 *
+ *                                                                         *
+ * Copyright (c) 2019-2021 by David Korth.                                 *
+ * SPDX-License-Identifier: GPL-2.0-or-later                               *
+ ***************************************************************************/
+
+#include "stdafx.h"
+
+#include "ImageDecoder.hpp"
+#include "ImageDecoder_p.hpp"
+
+#include "basisu_astc_decomp.h"
+
+// C++ STL classes.
+using std::array;
+
+namespace LibRpTexture { namespace ImageDecoder {
+
+/**
+ * Convert an ASTC 2D image to rp_image.
+ * @param width Image width
+ * @param height Image height
+ * @param img_buf PVRTC image buffer
+ * @param img_siz Size of image data
+ * @param block_x ASTC block size, X value
+ * @param block_y ASTC block size, Y value
+ * @return rp_image, or nullptr on error.
+ */
+ATTR_ACCESS_SIZE(read_only, 3, 4)
+rp_image *fromASTC(int width, int height,
+	const uint8_t *RESTRICT img_buf, int img_siz,
+	uint8_t block_x, uint8_t block_y)
+{
+	// Verify parameters.
+	assert(img_buf != nullptr);
+	assert(width > 0);
+	assert(height > 0);
+
+	// ASTC block size is always 128-bit.
+	// Based on the X and Y parameters, calculate the expected
+	// total compressed image size.
+	unsigned int texelsInBlock =
+		static_cast<unsigned int>(block_x) * static_cast<unsigned int>(block_y);
+
+	// Multiply (width * height) by texelsInBlock, then divide by 128 to get the actual size.
+	// NOTE: The image size doesn't need to be aligned to the block size,
+	// but the decompression buffer does need to be aligned.
+	int physWidth = width;
+	int physHeight = height;
+	if (physWidth % block_x != 0) {
+		physWidth += (block_x - (physWidth % block_x));
+	}
+	if (physHeight % block_y != 0) {
+		physHeight += (block_y - (physHeight % block_y));
+	}
+
+	// expected_size_in / texelsInBlock == number of blocks required
+	unsigned int expected_size_in = physWidth * physHeight;
+	unsigned int blocks_req = expected_size_in / texelsInBlock;
+	if (expected_size_in % texelsInBlock != 0) {
+		blocks_req++;
+	}
+	// Each block is 128 bits (16 bytes).
+	expected_size_in = blocks_req * 16;
+
+	assert(img_siz >= static_cast<int>(expected_size_in));
+	if (!img_buf || width <= 0 || height <= 0 ||
+	    img_siz < static_cast<int>(expected_size_in))
+	{
+		return nullptr;
+	}
+
+	// Create an rp_image.
+	rp_image *const img = new rp_image(physWidth, physHeight, rp_image::Format::ARGB32);
+	if (!img->isValid()) {
+		// Could not allocate the image.
+		img->unref();
+		return nullptr;
+	}
+
+	// Basis Universal's ASTC decoder handles one block at a time,
+	// so we'll need to use a tiled decode loop.
+
+	// Calculate the total number of tiles.
+	const unsigned int tilesX = static_cast<unsigned int>(physWidth / block_x);
+	const unsigned int tilesY = static_cast<unsigned int>(physHeight / block_y);
+
+	// Temporary tile buffer.
+	// NOTE: Largest ASTC format is 12x12.
+	array<uint32_t, 12*12> tileBuf;
+	const int stride_px = img->stride() / sizeof(uint32_t);
+	uint32_t *const pImgBits = static_cast<uint32_t*>(img->bits());
+
+	for (unsigned int y = 0; y < tilesY; y++) {
+		for (unsigned int x = 0; x < tilesX; x++, img_buf += 16) {
+			// Decode the tile from ASTC.
+			bool bRet = basisu_astc::astc::decompress(
+				reinterpret_cast<uint8_t*>(tileBuf.data()), img_buf,
+				false,	// TODO: sRGB scaling?
+				block_x, block_y);
+			if (!bRet) {
+				// ASTC decompression error.
+				img->unref();
+				return nullptr;
+			}
+
+			// Blit the tile to the main image buffer.
+			// NOTE: Not using BlitTile because ASTC has lots of different tile sizes.
+
+			// Go to the first pixel for this tile.
+			uint32_t *pImgBuf = pImgBits;
+			pImgBuf += (y * block_y) * stride_px;
+			pImgBuf += (x * block_x);
+
+			const uint32_t *pTileBuf = tileBuf.data();
+			for (unsigned int ty = block_y; ty > 0; ty--) {
+				memcpy(pImgBuf, pTileBuf, (block_x * sizeof(uint32_t)));
+				pImgBuf += stride_px;
+				pTileBuf += block_x;
+			}
+		}
+	}
+
+	if (width < physWidth || height < physHeight) {
+		// Shrink the image.
+		img->shrink(width, height);
+	}
+
+	// Set the sBIT metadata.
+	// NOTE: Assuming ASTC always has alpha for now.
+	static const rp_image::sBIT_t sBIT  = {8,8,8,0,8};
+	img->set_sBIT(&sBIT);
+
+	// Image has been converted.
+	return img;
+}
+
+} }

src/librptexture/fileformat/GodotSTEX.cpp

@@ -7,6 +7,8 @@
  ***************************************************************************/
 
 #include "stdafx.h"
+#include "config.librptexture.h"
+
 #include "GodotSTEX.hpp"
 #include "FileFormat_p.hpp"
 
@@ -163,6 +165,9 @@ unsigned int GodotSTEXPrivate::calcImageSize(STEX_Format_e format, unsigned int
 		Align4Divide2,
 		Align4,
 
+		// ASTC requires aligned blocks.
+		Align8Divide4,
+
 		Max
 	};
 
@@ -215,7 +220,8 @@ unsigned int GodotSTEXPrivate::calcImageSize(STEX_Format_e format, unsigned int
 		OpCode::Divide2,	// STEX_FORMAT_ETC2_RGB8A1	// TODO: Verify; Align4?
 
 		// Proprietary formats used in Sonic Colors Ultimate.
-		OpCode::Divide4,	// STEX_FORMAT_SCU_ASTC_8x8	// 8x8 == 2bpp
+		// FIXME: Other ASTC variants need a more complicated calculation.
+		OpCode::Align8Divide4,	// STEX_FORMAT_SCU_ASTC_8x8	// 8x8 == 2bpp
 	};
 	static_assert(ARRAY_SIZE(mul_tbl) == STEX_FORMAT_MAX,
 		"mul_tbl[] is not the correct size.");
@@ -257,6 +263,10 @@ unsigned int GodotSTEXPrivate::calcImageSize(STEX_Format_e format, unsigned int
 		case OpCode::Align4:
 			expected_size = ALIGN_BYTES(4, width) * ALIGN_BYTES(4, height);
 			break;
+
+		case OpCode::Align8Divide4:
+			expected_size = ALIGN_BYTES(8, width) * ALIGN_BYTES(8, height) / 4;
+			break;
 	}
 
 	return expected_size;
@@ -368,6 +378,15 @@ const rp_image *GodotSTEXPrivate::loadImage(int mip)
 				stexHeader.width, height,
 				buf.get(), expected_size);
 			break;
+
+#ifdef ENABLE_ASTC
+		case STEX_FORMAT_SCU_ASTC_8x8:
+			img = ImageDecoder::fromASTC(
+				stexHeader.width, height,
+				buf.get(), expected_size,
+				8, 8);
+			break;
+#endif /* ENABLE_ASTC */
 	}
 
 	mipmaps[mip] = img;