Implementation of CGBitmapContext.

Added custom iwic bitmap to support copying, and backed data buffer.
Added colour conversion format check for pixel formats.
Added tests to draw, render and validate changes.
CGImage changed to use OnLoad caching.

Frameworks/CoreGraphics/CGContext.mm

@@ -1,6 +1,6 @@
 //******************************************************************************
 //
-// Copyright (c) 2016 Microsoft Corporation. All rights reserved.
+// Copyright (c) Microsoft. All rights reserved.
 //
 // This code is licensed under the MIT License (MIT).
 //
@@ -25,9 +25,12 @@
 #import <CoreGraphics/CGLayer.h>
 #import <CoreGraphics/CGAffineTransform.h>
 #import <CoreGraphics/CGGradient.h>
+#import <LoggingNative.h>
+#import <CoreGraphics/D2DWrapper.h>
 #import "CGColorSpaceInternal.h"
 #import "CGContextInternal.h"
 #import "CGPathInternal.h"
+#import "CGIWICBitmap.h"
 
 #import <CFCppBase.h>
 
@@ -37,8 +40,6 @@
 #import <d2d1effects_2.h>
 #import <wrl/client.h>
 #include <COMIncludes_end.h>
-#import <LoggingNative.h>
-#import <CoreGraphics/D2DWrapper.h>
 
 #import <list>
 #import <vector>
@@ -1937,78 +1938,144 @@ inline void SetImage(CGImageRef image) {
 
 /**
  @Status Caveat
- @Notes Limited bitmap formats available. Decode, shouldInterpolate, intent parameters
- and some byte orders ignored.
- */
+ We only support formats that are 32 bits per pixel, colorspace and bitmapinfo that are ARGB.
+*/
 CGContextRef CGBitmapContextCreate(void* data,
                                    size_t width,
                                    size_t height,
                                    size_t bitsPerComponent,
                                    size_t bytesPerRow,
                                    CGColorSpaceRef colorSpace,
                                    CGBitmapInfo bitmapInfo) {
-    UNIMPLEMENTED();
-    return nullptr;
+    return CGBitmapContextCreateWithData(data, width, height, bitsPerComponent, bytesPerRow, colorSpace, bitmapInfo, nullptr, nullptr);
+}
+
+/**
+ @Status Caveat
+ @Notes releaseCallback and releaseInfo is ignored.
+ We only support formats that are 32 bits per pixel, colorspace and bitmapinfo that are ARGB.
+*/
+CGContextRef CGBitmapContextCreateWithData(void* data,
+                                           size_t width,
+                                           size_t height,
+                                           size_t bitsPerComponent,
+                                           size_t bytesPerRow,
+                                           CGColorSpaceRef space,
+                                           uint32_t bitmapInfo,
+                                           CGBitmapContextReleaseDataCallback releaseCallback,
+                                           void* releaseInfo) {
+    RETURN_NULL_IF(!width);
+    RETURN_NULL_IF(!height);
+    RETURN_NULL_IF(!space);
+
+    // bitsperpixel = ((bytesPerRow/width) * 8bits/byte)
+    size_t bitsPerPixel = ((bytesPerRow / width) << 3);
+    REFGUID pixelFormat = _CGImageGetWICPixelFormatFromImageProperties(bitsPerComponent, bitsPerPixel, space, bitmapInfo);
+
+    if (!_CGIsValidRenderTargetPixelFormat(pixelFormat)) {
+        UNIMPLEMENTED_WITH_MSG("CGBitmapContext does not currently support conversion and can only render into 32bpp PRGBA buffers.");
+        return nullptr;
+    }
+
+    // if data is null, enough memory is allocated via CGIWICBitmap
+    ComPtr<IWICBitmap> customBitmap = Make<CGIWICBitmap>(data, pixelFormat, height, width);
+    RETURN_NULL_IF(!customBitmap);
+
+    woc::unique_cf<CGImageRef> image(_CGImageCreateWithWICBitmap(customBitmap.Get()));
+    RETURN_NULL_IF(!image);
+
+    ComPtr<ID2D1Factory> factory;
+    RETURN_NULL_IF_FAILED(_CGGetD2DFactory(&factory));
+
+    ComPtr<ID2D1RenderTarget> renderTarget;
+    RETURN_NULL_IF_FAILED(factory->CreateWicBitmapRenderTarget(customBitmap.Get(), D2D1::RenderTargetProperties(), &renderTarget));
+    return _CGBitmapContextCreateWithRenderTarget(renderTarget.Get(), image.get());
+}
+
+/**
+ @Status Interoperable
+*/
+CGBitmapInfo CGBitmapContextGetBitmapInfo(CGContextRef context) {
+    NOISY_RETURN_IF_NULL(context, kCGBitmapByteOrderDefault);
+    return CGImageGetBitmapInfo(CGBitmapContextGetImage(context));
+}
+
+/**
+ @Status Interoperable
+*/
+CGImageAlphaInfo CGBitmapContextGetAlphaInfo(CGContextRef context) {
+    NOISY_RETURN_IF_NULL(context, kCGImageAlphaNone);
+    return CGImageGetAlphaInfo(CGBitmapContextGetImage(context));
+}
+
+/**
+ @Status Interoperable
+*/
+size_t CGBitmapContextGetBitsPerComponent(CGContextRef context) {
+    NOISY_RETURN_IF_NULL(context, 0);
+    return CGImageGetBitsPerComponent(CGBitmapContextGetImage(context));
+}
+
+/**
+ @Status Interoperable
+*/
+size_t CGBitmapContextGetBitsPerPixel(CGContextRef context) {
+    NOISY_RETURN_IF_NULL(context, 0);
+    return CGImageGetBitsPerPixel(CGBitmapContextGetImage(context));
 }
 
 /**
  @Status Interoperable
 */
 CGColorSpaceRef CGBitmapContextGetColorSpace(CGContextRef context) {
-    NOISY_RETURN_IF_NULL(context, StubReturn());
-    UNIMPLEMENTED();
-    return nullptr;
+    NOISY_RETURN_IF_NULL(context, nullptr);
+    return CGImageGetColorSpace(CGBitmapContextGetImage(context));
 }
 
 /**
  @Status Interoperable
 */
 size_t CGBitmapContextGetWidth(CGContextRef context) {
-    NOISY_RETURN_IF_NULL(context, StubReturn());
-    UNIMPLEMENTED();
-    return StubReturn();
+    NOISY_RETURN_IF_NULL(context, 0);
+    return CGImageGetWidth(CGBitmapContextGetImage(context));
 }
 
 /**
  @Status Interoperable
 */
 size_t CGBitmapContextGetHeight(CGContextRef context) {
-    NOISY_RETURN_IF_NULL(context, StubReturn());
-    UNIMPLEMENTED();
-    return StubReturn();
+    NOISY_RETURN_IF_NULL(context, 0);
+    return CGImageGetHeight(CGBitmapContextGetImage(context));
 }
 
 /**
  @Status Interoperable
 */
 size_t CGBitmapContextGetBytesPerRow(CGContextRef context) {
-    NOISY_RETURN_IF_NULL(context, StubReturn());
-    UNIMPLEMENTED();
-    return StubReturn();
+    NOISY_RETURN_IF_NULL(context, 0);
+    return CGImageGetBytesPerRow(CGBitmapContextGetImage(context));
 }
 
 /**
  @Status Interoperable
 */
 void* CGBitmapContextGetData(CGContextRef context) {
-    NOISY_RETURN_IF_NULL(context, StubReturn());
-    UNIMPLEMENTED();
-    return StubReturn();
+    NOISY_RETURN_IF_NULL(context, nullptr);
+    return _CGImageGetRawBytes(CGBitmapContextGetImage(context));
 }
 
 /**
  @Status Caveat
- @Notes Has no copy-on-write semantics; bitmap returned is the source bitmap representing
+ @Notes Has no copy-on-write semantics; bitmap returned is the copy of the source bitmap representing
         the CGContext
 */
 CGImageRef CGBitmapContextCreateImage(CGContextRef context) {
-    NOISY_RETURN_IF_NULL(context, StubReturn());
-    UNIMPLEMENTED();
-    return StubReturn();
+    NOISY_RETURN_IF_NULL(context, nullptr);
+    return CGImageCreateCopy(CGBitmapContextGetImage(context));
 }
 
 CGImageRef CGBitmapContextGetImage(CGContextRef context) {
-    NOISY_RETURN_IF_NULL(context, StubReturn());
+    NOISY_RETURN_IF_NULL(context, nullptr);
     if (CFGetTypeID(context) != __CGBitmapContext::GetTypeID()) {
         TraceError(TAG, L"Image requested from non-bitmap CGContext.");
         return nullptr;

Frameworks/CoreGraphics/CGImage.mm

@@ -121,7 +121,7 @@ CGImageRef CGImageCreateCopy(CGImageRef ref) {
 
     ComPtr<IWICBitmap> image;
 
-    RETURN_NULL_IF_FAILED(imageFactory->CreateBitmapFromSource(ref->ImageSource().Get(), WICBitmapCacheOnDemand, &image));
+    RETURN_NULL_IF_FAILED(imageFactory->CreateBitmapFromSource(ref->ImageSource().Get(), WICBitmapCacheOnLoad, &image));
 
     CGImageRef imageRef = __CGImage::CreateInstance();
     imageRef->SetImageSource(image)
@@ -225,7 +225,7 @@ CGColorSpaceRef CGImageGetColorSpace(CGImageRef img) {
  @Status Interoperable
 */
 CGBitmapInfo CGImageGetBitmapInfo(CGImageRef img) {
-    RETURN_RESULT_IF_NULL(img, 0);
+    RETURN_RESULT_IF_NULL(img, kCGBitmapByteOrderDefault);
     return img->BitmapInfo();
 }
 
@@ -375,6 +375,20 @@ CGImageRef CGImageCreateWithMaskingColors(CGImageRef image, const CGFloat* compo
 
 #pragma region WIC_HELPERS
 
+bool _CGIsValidRenderTargetPixelFormat(WICPixelFormatGUID pixelFormat) {
+    auto iterator = s_ValidRenderTargetPixelFormat.find(pixelFormat);
+    return iterator != s_ValidRenderTargetPixelFormat.end();
+}
+
+const __CGImagePixelProperties* _CGGetPixelFormatProperties(WICPixelFormatGUID pixelFormat) {
+    RETURN_NULL_IF(pixelFormat == GUID_WICPixelFormatUndefined);
+
+    auto iterator = s_PixelFormats.find(pixelFormat);
+    RETURN_NULL_IF(iterator == s_PixelFormats.end());
+
+    return &iterator->second;
+}
+
 IWICBitmap* _CGImageGetImageSource(CGImageRef image) {
     RETURN_NULL_IF(!image);
     return image->ImageSource().Get();
@@ -424,7 +438,7 @@ CGImageRef _CGImageCreateCopyWithPixelFormat(CGImageRef image, WICPixelFormatGUI
         image->ImageSource().Get(), pixelFormat, WICBitmapDitherTypeNone, nullptr, 0.f, WICBitmapPaletteTypeMedianCut));
 
     ComPtr<IWICBitmap> convertedImage;
-    RETURN_NULL_IF_FAILED(imageFactory->CreateBitmapFromSource(converter.Get(), WICBitmapCacheOnDemand, &convertedImage));
+    RETURN_NULL_IF_FAILED(imageFactory->CreateBitmapFromSource(converter.Get(), WICBitmapCacheOnLoad, &convertedImage));
 
     CGImageRef imageRef = __CGImage::CreateInstance();
     imageRef->SetImageSource(convertedImage);