Add `etcpak` library for faster ETC/ETC2/S3TC imports.

- `etc` module was renamed to `etcpak` and modified to use the new library.
- PKM importer is removed in the process, it's obsolete.
- Old library `etc2comp` is removed.
- S3TC compression no longer done via `squish` (but decompression still is).
- Slight modifications to etcpak sources for MinGW compatibility,
  to fix LLVM `-Wc++11-narrowing` errors, and to allow using vendored or
  system libpng.

Co-authored-by: Rémi Verschelde <rverschelde@gmail.com>

1 files changed, 0 insertions, 129 deletions

diff --git a/thirdparty/etc2comp/EtcBlock4x4Encoding_RGB8A1.h b/thirdparty/etc2comp/EtcBlock4x4Encoding_RGB8A1.h
deleted file mode 100644
index ff26e462f8..0000000000
--- a/thirdparty/etc2comp/EtcBlock4x4Encoding_RGB8A1.h
+++ /dev/null
@@ -1,129 +0,0 @@
-/*
- * Copyright 2015 The Etc2Comp Authors.
- *
- * 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.
- */
-
-#pragma once
-
-#include "EtcBlock4x4Encoding_RGB8.h"
-#include "EtcErrorMetric.h"
-#include "EtcBlock4x4EncodingBits.h"
-
-namespace Etc
-{
-
-	// ################################################################################
-	// Block4x4Encoding_RGB8A1
-	// RGB8A1 if not completely opaque or transparent
-	// ################################################################################
-
-	class Block4x4Encoding_RGB8A1 : public Block4x4Encoding_RGB8
-	{
-	public:
-
-		static const unsigned int TRANSPARENT_SELECTOR = 2;
-
-		Block4x4Encoding_RGB8A1(void);
-		virtual ~Block4x4Encoding_RGB8A1(void);
-
-		virtual void InitFromSource(Block4x4 *a_pblockParent,
-									ColorFloatRGBA *a_pafrgbaSource,
-									unsigned char *a_paucEncodingBits,
-									ErrorMetric a_errormetric);
-
-		virtual void InitFromEncodingBits(Block4x4 *a_pblockParent,
-											unsigned char *a_paucEncodingBits,
-											ColorFloatRGBA *a_pafrgbaSource,
-											ErrorMetric a_errormetric);
-
-		virtual void PerformIteration(float a_fEffort);
-
-		virtual void SetEncodingBits(void);
-
-		void InitFromEncodingBits_ETC1(Block4x4 *a_pblockParent,
-										unsigned char *a_paucEncodingBits,
-										ColorFloatRGBA *a_pafrgbaSource,
-										ErrorMetric a_errormetric);
-
-		void InitFromEncodingBits_T(void);
-		void InitFromEncodingBits_H(void);
-
-		void PerformFirstIteration(void);
-
-		void Decode_ETC1(void);
-		void DecodePixels_T(void);
-		void DecodePixels_H(void);
-		void SetEncodingBits_ETC1(void);
-		void SetEncodingBits_T(void);
-		void SetEncodingBits_H(void);
-
-	protected:
-
-		bool m_boolOpaque;				// all source pixels have alpha >= 0.5
-		bool m_boolTransparent;			// all source pixels have alpha < 0.5
-		bool m_boolPunchThroughPixels;	// some source pixels have alpha < 0.5
-
-		static float s_aafCwOpaqueUnsetTable[CW_RANGES][SELECTORS];
-
-	private:
-
-		void TryDifferential(bool a_boolFlip, unsigned int a_uiRadius,
-								int a_iGrayOffset1, int a_iGrayOffset2);
-		void TryDifferentialHalf(DifferentialTrys::Half *a_phalf);
-
-		void TryT(unsigned int a_uiRadius);
-		void TryT_BestSelectorCombination(void);
-		void TryH(unsigned int a_uiRadius);
-		void TryH_BestSelectorCombination(void);
-
-		void TryDegenerates1(void);
-		void TryDegenerates2(void);
-		void TryDegenerates3(void);
-		void TryDegenerates4(void);
-
-	};
-
-	// ################################################################################
-	// Block4x4Encoding_RGB8A1_Opaque
-	// RGB8A1 if all pixels have alpha==1
-	// ################################################################################
-
-	class Block4x4Encoding_RGB8A1_Opaque : public Block4x4Encoding_RGB8A1
-	{
-	public:
-
-		virtual void PerformIteration(float a_fEffort);
-
-		void PerformFirstIteration(void);
-
-	private:
-
-	};
-
-	// ################################################################################
-	// Block4x4Encoding_RGB8A1_Transparent
-	// RGB8A1 if all pixels have alpha==0
-	// ################################################################################
-
-	class Block4x4Encoding_RGB8A1_Transparent : public Block4x4Encoding_RGB8A1
-	{
-	public:
-
-		virtual void PerformIteration(float a_fEffort);
-
-	private:
-
-	};
-
-} // namespace Etc