Update build instructions for Skia m96 & Apple Silicon (#2451)

CMakeLists.txt

@@ -31,8 +31,9 @@ set(CMAKE_USER_MAKE_RULES_OVERRIDE_CXX ${CMAKE_CURRENT_SOURCE_DIR}/laf/cmake/cxx
 project(aseprite C CXX)
 
 if(CMAKE_CXX_COMPILER_ID STREQUAL "AppleClang")
-  # As we compile with CMAKE_OSX_DEPLOYMENT_TARGET=10.7, we have to
-  # explicitly say that we want to use libc++ instead of the GNU libstdc++
+  # As we compile with CMAKE_OSX_DEPLOYMENT_TARGET=10.9, we have to
+  # explicitly say that we want to use libc++ instead of the GNU
+  # libstdc++
   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -stdlib=libc++")
 endif()
 
@@ -277,15 +278,7 @@ include_directories(${FREETYPE_INCLUDE_DIRS})
 if(USE_SHARED_HARFBUZZ)
   find_package(HarfBuzz)
 else()
-  if(LAF_BACKEND STREQUAL "skia")
-    # Use the Skia harfbuzz (it's a modified version with C++11
-    # mutexes).
-    add_definitions(-DHAVE_CONFIG_OVERRIDE_H=1)
-    set(HARFBUZZ_LIBRARIES ${SKIA_HARFBUZZ_LIBRARY})
-    set(HARFBUZZ_INCLUDE_DIRS
-      ${SKIA_DIR}/third_party/harfbuzz
-      ${SKIA_DIR}/third_party/externals/harfbuzz/src)
-  else()
+  if(NOT LAF_BACKEND STREQUAL "skia")
     set(HARFBUZZ_LIBRARIES harfbuzz)
     set(HARFBUZZ_INCLUDE_DIRS ${HARFBUZZ_DIR}/src)
   endif()
@@ -348,6 +341,16 @@ set(LAF_WITH_TESTS ${ENABLE_TESTS} CACHE BOOL "Enable LAF tests")
 set(UNDO_TESTS     ${ENABLE_TESTS} CACHE BOOL "Enable undo tests")
 
 add_subdirectory(laf)
+
+# Use the Skia harfbuzz (it's a modified version with C++11 mutexes).
+if(LAF_BACKEND STREQUAL "skia")
+  add_definitions(-DHAVE_CONFIG_OVERRIDE_H=1)
+  set(HARFBUZZ_LIBRARIES ${SKIA_HARFBUZZ_LIBRARY})
+  set(HARFBUZZ_INCLUDE_DIRS
+    ${SKIA_DIR}/third_party/harfbuzz
+    ${SKIA_DIR}/third_party/externals/harfbuzz/src)
+endif()
+
 add_subdirectory(src)
 
 ######################################################################

INSTALL.md

@@ -163,7 +163,7 @@ Run `cmake` with the following parameters and then `ninja`:
       -DCMAKE_BUILD_TYPE=RelWithDebInfo \
       -DCMAKE_OSX_ARCHITECTURES=x86_64 \
       -DCMAKE_OSX_DEPLOYMENT_TARGET=10.9 \
-      -DCMAKE_OSX_SYSROOT=/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.15.sdk \
+      -DCMAKE_OSX_SYSROOT=/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk \
       -DLAF_BACKEND=skia \
       -DSKIA_DIR=$HOME/deps/skia \
       -DSKIA_LIBRARY_DIR=$HOME/deps/skia/out/Release-x64 \
@@ -175,9 +175,28 @@ Run `cmake` with the following parameters and then `ninja`:
 In this case, `$HOME/deps/skia` is the directory where Skia was
 compiled or downloaded.  Make sure that `CMAKE_OSX_SYSROOT` is
 pointing to the correct SDK directory (in this case
-`/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.15.sdk`),
+`/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk`),
 but it could be different in your Mac.
 
+### Apple Silicon
+
+If you running macOS on an ARM64/AArch64/Apple Silicon Mac (e.g. M1),
+you can compile a native ARM64 version of Aseprite following the same
+steps as above but when we call `cmake`, we have some differences:
+
+    cmake \
+      -DCMAKE_BUILD_TYPE=RelWithDebInfo \
+      -DCMAKE_OSX_ARCHITECTURES=arm64 \
+      -DCMAKE_OSX_DEPLOYMENT_TARGET=11.0 \
+      -DCMAKE_OSX_SYSROOT=/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk \
+      -DLAF_BACKEND=skia \
+      -DSKIA_DIR=$HOME/deps/skia \
+      -DSKIA_LIBRARY_DIR=$HOME/deps/skia/out/Release-arm64 \
+      -DSKIA_LIBRARY=$HOME/deps/skia/out/Release-arm64/libskia.a \
+      -DPNG_ARM_NEON:STRING=on \
+      -G Ninja \
+      ..
+
 ### Issues with Retina displays
 
 If you have a Retina display, check the following issue:
@@ -204,6 +223,12 @@ Run `cmake` with the following parameters and then `ninja`:
 In this case, `$HOME/deps/skia` is the directory where Skia was
 compiled or uncompressed.
 
+### GCC compiler
+
+In case that you are using the pre-compiled Skia version, you will
+need to use the Clang compiler to compile Aseprite. Only if you
+compile Skia with GCC, you will be able to compile Aseprite with GCC.
+
 # Using shared third party libraries
 
 If you don't want to use the embedded code of third party libraries

third_party/CMakeLists.txt

@@ -90,7 +90,7 @@ if(NOT USE_SHARED_FREETYPE)
   endif()
 endif()
 
-if(NOT USE_SHARED_HARFBUZZ)
+if(NOT USE_SHARED_HARFBUZZ AND NOT LAF_BACKEND STREQUAL "skia")
   if(NOT USE_SHARED_FREETYPE)
     set(ENV{FREETYPE_DIR} ${FREETYPE_DIR})
   endif()