Merge #1705 to CGD2D (#1750)

* CoreText Performance: Call ID2D1RenderTarget::BeginDraw()/EndDraw() f… (#1705)

* CoreText Performance: Call ID2D1RenderTarget::BeginDraw()/EndDraw() fewer times

Fixes #1620

* - Added Begin/EndDraw pairs to a few more places
- Mitigated an issue with cairo where ID2D1RenderTarget would sometimes cache a before state during begin draw,
  and wipe out any changes cairo made, breaking APIs like CGContextFillRect.
- Changed implementation/naming of the 'escape the current begin/end draw stack' functions

* Merge #1705 to CGD2D
 - Add PushBeginDraw/PopEndDraw pairs to UISegment, UIImage
   (not on develop since this likely would've actually hurt performance there)
 - Add Escape/Unescape pairs to CGContext areas where the target is changed

Fixes #1635

cr feedback

cr feedback

Frameworks/CoreGraphics/CGContext.mm

@@ -43,6 +43,7 @@
 #import <wrl/client.h>
 #include <COMIncludes_end.h>
 
+#import <atomic>
 #import <list>
 #import <vector>
 #import <stack>
@@ -258,6 +259,13 @@ inline HRESULT GetTarget(ID2D1Image** pTarget) {
     woc::unique_cf<CGColorSpaceRef> _fillColorSpace;
     woc::unique_cf<CGColorSpaceRef> _strokeColorSpace;
 
+    // Keeps track of the depth of a 'stack' of PushBeginDraw/PopEndDraw calls
+    // Since nothing needs to actually be put on a stack, just increment a counter insteads
+    std::atomic_uint32_t _beginEndDrawDepth = { 0 };
+
+    // Keeps track of the depth of a 'stack' of (Un)EscapeBeginEndDrawStack calls
+    std::atomic_uint32_t _escapeBeginEndDrawDepth = { 0 };
+
     inline HRESULT _SaveD2DDrawingState(ID2D1DrawingStateBlock** pDrawingState) {
         RETURN_HR_IF(E_POINTER, !pDrawingState);
 
@@ -380,6 +388,32 @@ inline bool ShouldDraw() {
         return CurrentGState().ShouldDraw();
     }
 
+    inline void PushBeginDraw() {
+        if ((_beginEndDrawDepth)++ == 0) {
+            deviceContext->BeginDraw();
+        }
+    }
+
+    inline HRESULT PopEndDraw() {
+        if (--(_beginEndDrawDepth) == 0) {
+            RETURN_IF_FAILED(deviceContext->EndDraw());
+        }
+        return S_OK;
+    }
+
+    inline HRESULT EscapeBeginEndDrawStack() {
+        if ((_beginEndDrawDepth > 0) && ((_escapeBeginEndDrawDepth)++ == 0)) {
+            RETURN_IF_FAILED(deviceContext->EndDraw());
+        }
+        return S_OK;
+    }
+
+    inline void UnescapeBeginEndDrawStack() {
+        if ((_beginEndDrawDepth > 0) && (--(_escapeBeginEndDrawDepth) == 0)) {
+            deviceContext->BeginDraw();
+        }
+    }
+
     HRESULT Clip(CGPathDrawingMode pathMode);
 
     HRESULT PushLayer(CGRect* rect = nullptr);
@@ -503,7 +537,9 @@ void CGContextSynchronize(CGContextRef context) {
     ComPtr<ID2D1CommandList> commandList;
     RETURN_IF_FAILED(deviceContext->CreateCommandList(&commandList));
 
+    EscapeBeginEndDrawStack();
     deviceContext->SetTarget(commandList.Get());
+    UnescapeBeginEndDrawStack();
 
     // Copy the current layer's state to the new layer.
     auto& oldLayer = _layerStack.top();
@@ -576,7 +612,9 @@ void CGContextSynchronize(CGContextRef context) {
     ComPtr<ID2D1Image> incomingImageTarget;
     RETURN_IF_FAILED(incomingLayer.GetTarget(&incomingImageTarget));
 
+    EscapeBeginEndDrawStack();
     deviceContext->SetTarget(incomingImageTarget.Get());
+    UnescapeBeginEndDrawStack();
 
     RETURN_IF_FAILED(DrawImage(outgoingCommandList.Get()));
 
@@ -2156,8 +2194,9 @@ void CGContextClearRect(CGContextRef context, CGRect rect) {
     ComPtr<ID2D1CommandList> commandList;
     RETURN_IF_FAILED(deviceContext->CreateCommandList(&commandList));
 
-    deviceContext->BeginDraw();
+    EscapeBeginEndDrawStack();
     deviceContext->SetTarget(commandList.Get());
+    deviceContext->BeginDraw();
 
     CGAffineTransform transform = CGAffineTransformIdentity;
     switch (coordinateMode) {
@@ -2184,6 +2223,7 @@ void CGContextClearRect(CGContextRef context, CGRect rect) {
     RETURN_IF_FAILED(commandList->Close());
 
     deviceContext->SetTarget(originalTarget.Get());
+    UnescapeBeginEndDrawStack();
 
     *outCommandList = commandList.Detach();
     return S_OK;
@@ -2197,7 +2237,9 @@ void CGContextClearRect(CGContextRef context, CGRect rect) {
         return S_OK;
     }
 
-    deviceContext->BeginDraw();
+    PushBeginDraw();
+    // TODO GH#1194: We will need to re-evaluate Direct2D's D2DERR_RECREATE when we move to HW acceleration.
+    auto popEnd = wil::ScopeExit([this]() { this->PopEndDraw(); });
 
     bool layer = false;
     if (state.clippingGeometry || !IS_NEAR(state.globalAlpha, 1.0, .0001f) || state.opacityBrush) {
@@ -2225,9 +2267,6 @@ void CGContextClearRect(CGContextRef context, CGRect rect) {
         deviceContext->PopLayer();
     }
 
-    // TODO GH#1194: We will need to re-evaluate Direct2D's D2DERR_RECREATE when we move to HW acceleration.
-    RETURN_IF_FAILED(deviceContext->EndDraw());
-
     return S_OK;
 }
 
@@ -2933,3 +2972,23 @@ CGContextRef _CGBitmapContextCreateWithFormat(int width, int height, __CGSurface
     return StubReturn();
 }
 #pragma endregion
+
+#pragma region CGContextBeginDrawEndDraw
+
+void _CGContextPushBeginDraw(CGContextRef context) {
+    context->PushBeginDraw();
+}
+
+void _CGContextPopEndDraw(CGContextRef context) {
+    FAIL_FAST_IF_FAILED(context->PopEndDraw());
+}
+
+void _CGContextEscapeBeginEndDrawStack(CGContextRef context) {
+    FAIL_FAST_IF_FAILED(context->EscapeBeginEndDrawStack());
+}
+
+void _CGContextUnescapeBeginEndDrawStack(CGContextRef context) {
+    context->UnescapeBeginEndDrawStack();
+}
+
+#pragma endregion

Frameworks/CoreText/CTFrame.mm

@@ -19,6 +19,7 @@
 
 #import "DWriteWrapper_CoreText.h"
 #import "CoreTextInternal.h"
+#import "CGContextInternal.h"
 #import "CGPathInternal.h"
 
 const CFStringRef kCTFrameProgressionAttributeName = static_cast<CFStringRef>(@"kCTFrameProgressionAttributeName");
@@ -122,6 +123,9 @@ void CTFrameDraw(CTFrameRef frameRef, CGContextRef ctx) {
             ctx, CGAffineTransformMake(textMatrix.a, -textMatrix.b, textMatrix.c, -textMatrix.d, textMatrix.tx, textMatrix.ty));
         CGContextScaleCTM(ctx, 1.0f, -1.0f);
 
+        _CGContextPushBeginDraw(ctx);
+        auto popEnd = wil::ScopeExit([ctx]() { _CGContextPopEndDraw(ctx); });
+
         for (size_t i = 0; i < frame->_lineOrigins.size() && (frame->_lineOrigins[i].y < frame->_frameRect.size.height); ++i) {
             _CTLine* line = static_cast<_CTLine*>([frame->_lines objectAtIndex:i]);
             CGContextSetTextPosition(ctx, frame->_lineOrigins[i].x, frame->_lineOrigins[i].y);

Frameworks/CoreText/CTLine.mm

@@ -225,6 +225,9 @@ void CTLineDraw(CTLineRef lineRef, CGContextRef ctx) {
 
     _CTLine* line = static_cast<_CTLine*>(lineRef);
 
+    _CGContextPushBeginDraw(ctx);
+    auto popEnd = wil::ScopeExit([ctx]() { _CGContextPopEndDraw(ctx); });
+
     for (size_t i = 0; i < [line->_runs count]; ++i) {
         _CTRun* curRun = [line->_runs objectAtIndex:i];
         if (i > 0) {

Frameworks/QuartzCore/CALayer.mm

@@ -393,6 +393,13 @@ - (void)renderInContext:(CGContextRef)ctx {
     [self layoutIfNeeded];
 
     CGContextSaveGState(ctx);
+    _CGContextPushBeginDraw(ctx);
+
+    auto popEnd = wil::ScopeExit([ctx]() {
+        _CGContextPopEndDraw(ctx);
+        CGContextRestoreGState(ctx);
+    });
+
     CGContextTranslateCTM(ctx, priv->position.x, priv->position.y);
     CGContextTranslateCTM(ctx, -priv->bounds.size.width * priv->anchorPoint.x, -priv->bounds.size.height * priv->anchorPoint.y);
     CGRect destRect;
@@ -435,8 +442,6 @@ - (void)renderInContext:(CGContextRef)ctx {
     LLTREE_FOREACH(curLayer, priv) {
         [curLayer->self renderInContext:ctx];
     }
-
-    CGContextRestoreGState(ctx);
 }
 
 /**
@@ -521,6 +526,13 @@ - (void)display {
         CGImageRef target = CGBitmapContextGetImage(drawContext);
 
         CGContextRetain(drawContext);
+        _CGContextPushBeginDraw(drawContext);
+
+        auto popEnd = wil::ScopeExit([drawContext]() {
+            _CGContextPopEndDraw(drawContext);
+            CGContextRelease(drawContext);
+        });
+
         CGImageRetain(target);
         priv->savedContext = drawContext;
 
@@ -561,7 +573,6 @@ - (void)display {
         }
 
         CGContextReleaseLock(drawContext);
-        CGContextRelease(drawContext);
 
         // If we've drawn anything, set it as our contents
         if (!CGContextIsDirty(drawContext)) {
@@ -2371,7 +2382,7 @@ CGPoint _legacyConvertPoint(CGPoint point, CALayer* fromLayer, CALayer* toLayer)
     //  Convert the point to center-based position
     point.x -= fromLayer->priv->bounds.size.width * fromLayer->priv->anchorPoint.x;
     point.y -= fromLayer->priv->bounds.size.height * fromLayer->priv->anchorPoint.y;
- 
+
     //  Convert to world-view
     CGAffineTransform fromTransform;
     GetLayerTransform(fromLayer, &fromTransform);
@@ -2381,11 +2392,11 @@ CGPoint _legacyConvertPoint(CGPoint point, CALayer* fromLayer, CALayer* toLayer)
     GetLayerTransform(toLayer, &toTransform);
     toTransform = CGAffineTransformInvert(toTransform);
     point = CGPointApplyAffineTransform(point, toTransform);
- 
+
     //  Convert the point from center-based position
     point.x += toLayer->priv->bounds.size.width * toLayer->priv->anchorPoint.x;
     point.y += toLayer->priv->bounds.size.height * toLayer->priv->anchorPoint.y;
- 
+
     return point;
 }
 
@@ -2439,10 +2450,16 @@ + (CGPoint)convertPoint:(CGPoint)point fromLayer:(CALayer*)fromLayer toLayer:(CA
         // How does our new convertPoint logic compare to the legacy logic?
         CGPoint legacyPoint = _legacyConvertPoint(point, fromLayer, toLayer);
         if (!_floatAlmostEqual(ret.x, legacyPoint.x) || !_floatAlmostEqual(ret.y, legacyPoint.y)) {
-            TraceWarning(TAG, L"convertPoint: The legacy point {%f, %f} did not match the new point {%f, %f}!", legacyPoint.x, legacyPoint.y, ret.x, ret.y);
+            TraceWarning(TAG,
+                         L"convertPoint: The legacy point {%f, %f} did not match the new point {%f, %f}!",
+                         legacyPoint.x,
+                         legacyPoint.y,
+                         ret.x,
+                         ret.y);
         }
 
-        TraceVerbose(TAG, L"convertPoint:{%f, %f} to:{%f, %f}, legacyPoint={%f, %f}", point.x, point.y, ret.x, ret.y, legacyPoint.x, legacyPoint.y);
+        TraceVerbose(
+            TAG, L"convertPoint:{%f, %f} to:{%f, %f}, legacyPoint={%f, %f}", point.x, point.y, ret.x, ret.y, legacyPoint.x, legacyPoint.y);
     }
 
     return ret;

Frameworks/UIKit/NSLayoutManager.mm

@@ -23,6 +23,7 @@
 #include <UIKit/UIGraphics.h>
 
 #include "CoreTextInternal.h"
+#include "CGContextInternal.h"
 
 #include <vector>
 #include <functional>
@@ -257,6 +258,9 @@ - (void)drawGlyphsForGlyphRange:(NSRange)range atPoint:(CGPoint)position {
     CGContextSaveGState(curCtx);
     CGContextSetTextMatrix(curCtx, CGAffineTransformMakeScale(1.0f, -1.0f));
 
+    _CGContextPushBeginDraw(curCtx);
+    auto popEnd = wil::ScopeExit([curCtx]() { _CGContextPopEndDraw(curCtx); });
+
     int count = [_ctLines count];
     for (int curLine = 0; curLine < count; curLine++) {
         CTLineRef line = (CTLineRef)_ctLines[curLine];

Frameworks/UIKit/NSString+UIKitAdditions.mm

@@ -22,6 +22,7 @@
 #import <Foundation/NSMutableDictionary.h>
 #import "CoreGraphics/CGContext.h"
 #import "CoreTextInternal.h"
+#import "CGContextInternal.h"
 #import "NSParagraphStyleInternal.h"
 #import <assert.h>
 #import "LoggingNative.h"
@@ -145,6 +146,8 @@ - (CGSize)drawInRect:(CGRect)rect withFont:(UIFont*)font lineBreakMode:(UILineBr
     }
 
     CGContextRef context = UIGraphicsGetCurrentContext();
+    _CGContextPushBeginDraw(context);
+    auto popEnd = wil::ScopeExit([context]() { _CGContextPopEndDraw(context); });
 
     // Invert text matrix so glyphs are drawn with correct orientation
     CGContextSetTextMatrix(context, CGAffineTransformMakeScale(1.0f, -1.0f));

Frameworks/UIKit/UIImage.mm

@@ -474,6 +474,12 @@ - (void)drawAtPoint:(CGPoint)point blendMode:(CGBlendMode)mode alpha:(float)alph
     RETURN_IF(!img);
 
     CGContextSaveGState(cur);
+    _CGContextPushBeginDraw(cur);
+
+    auto popEnd = wil::ScopeExit([cur]() {
+        _CGContextPopEndDraw(cur);
+        CGContextRestoreGState(cur);
+    });
 
     CGContextSetBlendMode(cur, mode);
     CGContextSetAlpha(cur, alpha);
@@ -493,8 +499,6 @@ - (void)drawAtPoint:(CGPoint)point blendMode:(CGBlendMode)mode alpha:(float)alph
     srcRect.size.height = -img_height;
 
     _CGContextDrawImageRect(cur, img, srcRect, pos);
-
-    CGContextRestoreGState(cur);
 }
 
 /**
@@ -672,14 +676,18 @@ - (void)drawInRect:(CGRect)pos blendMode:(CGBlendMode)mode alpha:(float)alpha {
     }
 
     CGContextSaveGState(ctx);
+    _CGContextPushBeginDraw(ctx);
+
+    auto popEnd = wil::ScopeExit([ctx]() {
+        _CGContextPopEndDraw(ctx);
+        CGContextRestoreGState(ctx);
+    });
 
     CGContextSetBlendMode(ctx, mode);
     CGContextSetAlpha(ctx, alpha);
 
     // Draw image and divide into patches if necessary
     drawPatches(ctx, self, &pos);
-
-    CGContextRestoreGState(ctx);
 }
 
 - (void)setOrientation:(UIImageOrientation)orientation {

Frameworks/UIKit/UISegment.mm

@@ -26,6 +26,7 @@
 #import <UIKit/UIView.h>
 #import <Foundation/NSString.h>
 #import <CoreGraphics/CGContext.h>
+#import "CGContextInternal.h"
 #import "UISegment.h"
 #import "UIViewInternal.h"
 #import "UISegmentedControlInternal.h"
@@ -224,26 +225,29 @@ - (id)drawRect:(CGRect)inRect {
         }
     }
 
+    CGContextRef ctx = UIGraphicsGetCurrentContext();
+
+    _CGContextPushBeginDraw(ctx);
+    auto popEnd = wil::ScopeExit([ctx]() { _CGContextPopEndDraw(ctx); });
+
     if (isOSTarget(@"7.0")) {
         if (_tintColor != nil) {
             if (_selected == 1) {
-                CGContextSetFillColorWithColor(UIGraphicsGetCurrentContext(), [_tintColor CGColor]);
-                CGContextFillRect(UIGraphicsGetCurrentContext(), bounds);
+                CGContextSetFillColorWithColor(ctx, [_tintColor CGColor]);
+                CGContextFillRect(ctx, bounds);
             }
             if ((_type & 2) == 0) {
                 CGRect rect = bounds;
                 float lineWidth = 1.0f;
 
                 rect.origin.x = rect.size.width - lineWidth;
                 rect.size.width = lineWidth;
-                CGContextSetFillColorWithColor(UIGraphicsGetCurrentContext(), [_tintColor CGColor]);
-                CGContextFillRect(UIGraphicsGetCurrentContext(), rect);
+                CGContextSetFillColorWithColor(ctx, [_tintColor CGColor]);
+                CGContextFillRect(ctx, rect);
             }
         }
     } else {
         if (!_noDefaultImages) {
-            CGContextRef ctx = UIGraphicsGetCurrentContext();
-
             if (_selected) {
                 // No border, just fill with background color
                 CGContextSetFillColorWithColor(ctx, [bgColor CGColor]);
@@ -293,7 +297,7 @@ - (id)drawRect:(CGRect)inRect {
     }
 
     if (_title != nil) {
-        CGContextSetFillColorWithColor(UIGraphicsGetCurrentContext(), [textColor CGColor]);
+        CGContextSetFillColorWithColor(ctx, [textColor CGColor]);
 
         CGSize size;
         CGRect rect;