From e89f654559793e5e4fabf657fe87656f581f7494 Mon Sep 17 00:00:00 2001
From: Sebastian Krzyszkowiak <dos@dosowisko.net>
Date: Thu, 24 Jan 2019 23:57:23 +0100
Subject: [PATCH] ImgToWebp: add ability to use lossless compression

Good for pixel art
---
 cmake/ImgToWebp.cmake     | 11 ++++++++---
 cmake/libsuperderpy.cmake |  9 +++++++--
 2 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/cmake/ImgToWebp.cmake b/cmake/ImgToWebp.cmake
index 052746c..289043e 100644
--- a/cmake/ImgToWebp.cmake
+++ b/cmake/ImgToWebp.cmake
@@ -14,20 +14,25 @@ if(CONVERT)
       else()
         set(resizecmd "")
       endif()
-      GetFromAssetCache(${CACHE} ${DATADIR}/${file} "${QUALITY}-${RESIZE}-${PARAMS}" CACHED HASH)
+      if (LOSSLESS)
+        set(losslesscmd -define webp:lossless=true)
+      else()
+        set(losslesscmd "")
+      endif()
+      GetFromAssetCache(${CACHE} ${DATADIR}/${file} "${LOSSLESS}-${QUALITY}-${RESIZE}-${PARAMS}" CACHED HASH)
       if (CACHED)
         file(REMOVE ${DATADIR}/${file})
         configure_file(${CACHED} ${DATADIR}/${filepath}.wbp COPYONLY)
         unset(CACHED)
       else()
         separate_arguments(PARAMS)
-        set(CONVERT_CMD ${CONVERT} ${file} -quality ${QUALITY} ${PARAMS} ${resizecmd} webp:${filepath}.wbp)
+        set(CONVERT_CMD ${CONVERT} ${file} -quality ${QUALITY} ${PARAMS} ${resizecmd} ${losslesscmd} webp:${filepath}.wbp)
         execute_process(COMMAND ${CONVERT_CMD} WORKING_DIRECTORY ${DATADIR} RESULT_VARIABLE CONVERT_RESULT)
         if(CONVERT_RESULT)
           message(WARNING "ERROR: ${CONVERT_RESULT}")
         else()
           file(REMOVE ${DATADIR}/${file})
-          AddToAssetCache(${CACHE} ${HASH} "${QUALITY}-${RESIZE}-${PARAMS}" "${DATADIR}/${filepath}.wbp")
+          AddToAssetCache(${CACHE} ${HASH} "${LOSSLESS}-${QUALITY}-${RESIZE}-${PARAMS}" "${DATADIR}/${filepath}.wbp")
         endif()
       endif()
     endif()
diff --git a/cmake/libsuperderpy.cmake b/cmake/libsuperderpy.cmake
index 19b2b04..0464d4b 100644
--- a/cmake/libsuperderpy.cmake
+++ b/cmake/libsuperderpy.cmake
@@ -330,13 +330,18 @@ if (NOT LIBSUPERDERPY_CONFIG_INCLUDED)
 			COMMAND ${CMAKE_COMMAND} -DDATADIR=${ASSET_PIPELINE_DATADIR} -DCACHE="${CMAKE_SOURCE_DIR}/.assetcache" -DBITRATE=${FLACTOOPUS_BITRATE} -P ${LIBSUPERDERPY_DIR}/cmake/FlacToOpus.cmake
 			USES_TERMINAL)
 
-		set(IMGTOWEBP_QUALITY "75" CACHE STRING "Quality of resulting WebP files")
+		option(IMGTOWEBP_LOSSLESS "Use lossless WebP compression" OFF)
+		if(IMGTOWEBP_LOSSLESS)
+			set(IMGTOWEBP_QUALITY "100" CACHE STRING "Quality of resulting WebP files")
+		else(IMGTOWEBP_LOSSLESS)
+			set(IMGTOWEBP_QUALITY "75" CACHE STRING "Quality of resulting WebP files")
+		endif(IMGTOWEBP_LOSSLESS)
 		set(IMGTOWEBP_RESIZE "" CACHE STRING "Value passed as -resize to ImageMagick (no resizing when empty)")
 		set(IMGTOWEBP_PARAMS "" CACHE STRING "Additional ImageMagick parameters")
 
 		add_custom_target(${LIBSUPERDERPY_GAMENAME}_img_to_webp
 			DEPENDS ${ASSET_PIPELINE_DEPEND}
-			COMMAND ${CMAKE_COMMAND} -DQUALITY="${IMGTOWEBP_QUALITY}" -DRESIZE="${IMGTOWEBP_RESIZE}" -DPARAMS="${IMGTOWEBP_PARAMS}" -DCACHE="${CMAKE_SOURCE_DIR}/.assetcache" -DDATADIR=${ASSET_PIPELINE_DATADIR} -P ${LIBSUPERDERPY_DIR}/cmake/ImgToWebp.cmake
+			COMMAND ${CMAKE_COMMAND} -DQUALITY="${IMGTOWEBP_QUALITY}" -DRESIZE="${IMGTOWEBP_RESIZE}" -DPARAMS="${IMGTOWEBP_PARAMS}" -DCACHE="${CMAKE_SOURCE_DIR}/.assetcache" -DLOSSLESS="${IMGTOWEBP_LOSSLESS}" -DDATADIR=${ASSET_PIPELINE_DATADIR} -P ${LIBSUPERDERPY_DIR}/cmake/ImgToWebp.cmake
 			USES_TERMINAL)
 
 	endif(ANDROID OR EMSCRIPTEN)