6 files changed, 40 insertions, 2 deletions
diff --git a/include/cru/osx/graphics/quartz/Convert.hpp b/include/cru/osx/graphics/quartz/Convert.hpp
new file mode 100644
index 00000000..9706dc00
--- /dev/null
+++ b/include/cru/osx/graphics/quartz/Convert.hpp
@@ -0,0 +1,9 @@
+#pragma once
+#include "cru/platform/Matrix.hpp"
+
+#include <CoreGraphics/CoreGraphics.h>
+
+namespace cru::platform::graphics::osx::quartz {
+  CGAffineTransform Convert(const Matrix& matrix);
+  Matrix Convert(const CGAffineTransform& matrix);
+}
diff --git a/include/cru/osx/graphics/quartz/Painter.hpp b/include/cru/osx/graphics/quartz/Painter.hpp
index 2d77ab3a..7f775210 100644
--- a/include/cru/osx/graphics/quartz/Painter.hpp
+++ b/include/cru/osx/graphics/quartz/Painter.hpp
@@ -8,7 +8,7 @@ namespace cru::platform::graphics::osx::quartz {
 class QuartzCGContextPainter : public OsxQuartzResource,
                                public virtual IPainter {
  public:
-  explicit QuartzCGContextPainter(CGContext* cg_context)
+  explicit QuartzCGContextPainter(CGContextRef cg_context)
       : cg_context_(cg_context) {}
 
  public:
@@ -36,6 +36,6 @@ class QuartzCGContextPainter : public OsxQuartzResource,
   void EndDraw() override;
 
  private:
-  CGContext* cg_context_;
+  CGContextRef cg_context_;
 };
 }  // namespace cru::platform::graphics::osx::quartz
diff --git a/src/osx/graphics/quartz/CMakeLists.txt b/src/osx/graphics/quartz/CMakeLists.txt
index 41577ad7..2d66c3e7 100644
--- a/src/osx/graphics/quartz/CMakeLists.txt
+++ b/src/osx/graphics/quartz/CMakeLists.txt
@@ -1,11 +1,13 @@
 set(CRU_OSX_GRAPHICS_NATIVE_INCLUDE_DIR ${CRU_INCLUDE_DIR}/cru/osx/graphics/quartz)
 
 add_library(cru_osx_graphics_quartz SHARED
+	Convert.cpp
 	Factory.cpp
 	Painter.cpp
 	Resource.cpp
 )
 target_sources(cru_osx_graphics_quartz PUBLIC
+	${CRU_OSX_GRAPHICS_NATIVE_INCLUDE_DIR}/Convert.hpp
 	${CRU_OSX_GRAPHICS_NATIVE_INCLUDE_DIR}/Factory.hpp
 	${CRU_OSX_GRAPHICS_NATIVE_INCLUDE_DIR}/Painter.hpp
 	${CRU_OSX_GRAPHICS_NATIVE_INCLUDE_DIR}/Resource.hpp
diff --git a/src/osx/graphics/quartz/Convert.cpp b/src/osx/graphics/quartz/Convert.cpp
new file mode 100644
index 00000000..95923083
--- /dev/null
+++ b/src/osx/graphics/quartz/Convert.cpp
@@ -0,0 +1,11 @@
+#include "cru/osx/graphics/quartz/Convert.hpp"
+
+namespace cru::platform::graphics::osx::quartz {
+CGAffineTransform Convert(const Matrix& matrix) {
+  return CGAffineTransformMake(matrix.m11, matrix.m12, matrix.m21, matrix.m22, matrix.m31, matrix.m32);
+}
+
+Matrix Convert(const CGAffineTransform& matrix) {
+  return Matrix(matrix.a, matrix.b, matrix.c, matrix.d, matrix.tx, matrix.ty);
+}
+}  // namespace cru::platform::graphics::osx::quartz
diff --git a/src/osx/graphics/quartz/Painter.cpp b/src/osx/graphics/quartz/Painter.cpp
index b3006a97..65cf9154 100644
--- a/src/osx/graphics/quartz/Painter.cpp
+++ b/src/osx/graphics/quartz/Painter.cpp
@@ -1 +1,16 @@
 #include "cru/osx/graphics/quartz/Painter.hpp"
+
+#include "cru/osx/graphics/quartz/Convert.hpp"
+
+namespace cru::platform::graphics::osx::quartz {
+  Matrix QuartzCGContextPainter::GetTransform() {
+    return Convert(CGContextGetCTM(cg_context_));
+  }
+  
+  void QuartzCGContextPainter::SetTransform(const Matrix& matrix)  {
+    auto old = CGContextGetCTM(cg_context_);
+    old = CGAffineTransformInvert(old);
+    CGContextConcatCTM(cg_context_, old);
+    CGContextConcatCTM(cg_context_, Convert(matrix));
+  }
+}
diff --git a/src/osx/graphics/quartz/Resource.cpp b/src/osx/graphics/quartz/Resource.cpp
index e69de29b..3ee09cdd 100644
--- a/src/osx/graphics/quartz/Resource.cpp
+++ b/src/osx/graphics/quartz/Resource.cpp
@@ -0,0 +1 @@
+#include "cru/osx/graphics/quartz/Resource.hpp"