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

Frameworks/CoreGraphics/CGContext.mm

@@ -258,6 +258,13 @@ 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);
 
@@ -2922,3 +2929,38 @@ CGContextRef _CGBitmapContextCreateWithFormat(int width, int height, __CGSurface
     return StubReturn();
 }
 #pragma endregion
+#pragma region CGContextBeginDrawEndDraw
+
+void _CGContextPushBeginDraw(CGContextRef ctx) {
+    if ((ctx->_beginEndDrawDepth)++ == 0) {
+        ID2D1RenderTarget* imgRenderTarget = ctx->Backing()->DestImage()->Backing()->GetRenderTarget();
+        THROW_HR_IF_NULL(E_UNEXPECTED, imgRenderTarget);
+        imgRenderTarget->BeginDraw();
+    }
+}
+
+void _CGContextPopEndDraw(CGContextRef ctx) {
+    if (--(ctx->_beginEndDrawDepth) == 0) {
+        ID2D1RenderTarget* imgRenderTarget = ctx->Backing()->DestImage()->Backing()->GetRenderTarget();
+        THROW_HR_IF_NULL(E_UNEXPECTED, imgRenderTarget);
+        THROW_IF_FAILED(imgRenderTarget->EndDraw());
+    }
+}
+
+void _CGContextEscapeBeginEndDrawStack(CGContextRef ctx) {
+    if ((ctx->_beginEndDrawDepth > 0) && ((ctx->_escapeBeginEndDrawDepth)++ == 0)) {
+        ID2D1RenderTarget* imgRenderTarget = ctx->Backing()->DestImage()->Backing()->GetRenderTarget();
+        THROW_HR_IF_NULL(E_UNEXPECTED, imgRenderTarget);
+        THROW_IF_FAILED(imgRenderTarget->EndDraw());
+    }
+}
+
+void _CGContextUnescapeBeginEndDrawStack(CGContextRef ctx) {
+    if ((ctx->_beginEndDrawDepth > 0) && (--(ctx->_escapeBeginEndDrawDepth) == 0)) {
+        ID2D1RenderTarget* imgRenderTarget = ctx->Backing()->DestImage()->Backing()->GetRenderTarget();
+        THROW_HR_IF_NULL(E_UNEXPECTED, imgRenderTarget);
+        imgRenderTarget->BeginDraw();
+    }
+}
+
+#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/UITabBarButton.mm

@@ -45,15 +45,17 @@ - (void)drawRect:(CGRect)pos {
     CGRect rect;
     rect = [self bounds];
 
+    CGContextRef context = UIGraphicsGetCurrentContext();
+
     id tabBar = [self superview];
     id selectedItem = [tabBar selectedItem];
     if (selectedItem == _item) {
         id selectionIndicatorImage = [tabBar selectionIndicatorImage];
         if (selectionIndicatorImage != nil) {
             [selectionIndicatorImage drawInRect:rect];
         } else {
-            CGContextSetFillColorWithColor(UIGraphicsGetCurrentContext(), (CGColorRef)[UIColor grayColor]);
-            CGContextFillRect(UIGraphicsGetCurrentContext(), rect);
+            CGContextSetFillColorWithColor(context, (CGColorRef)[UIColor grayColor]);
+            CGContextFillRect(context, rect);
         }
     }
 
@@ -107,16 +109,19 @@ - (void)drawRect:(CGRect)pos {
         clipRect.origin.y = 5.0f;
         clipRect.size.width = rect.size.width - clipRect.origin.x - 3.0f;
         clipRect.size.height = rect.size.height - clipRect.origin.y - 13.0f;
-        CGContextSaveGState(UIGraphicsGetCurrentContext());
-        CGContextClipToRect(UIGraphicsGetCurrentContext(), clipRect);
-        CGContextDrawImage(UIGraphicsGetCurrentContext(), drawRect, CGBitmapContextGetImage(context));
-        CGContextRestoreGState(UIGraphicsGetCurrentContext());
+        CGContextSaveGState(context);
+        CGContextClipToRect(context, clipRect);
+        CGContextDrawImage(context, drawRect, CGBitmapContextGetImage(context));
+        CGContextRestoreGState(context);
 
         CGContextRelease(context);
     }
 
     NSString* title = [_item title];
     if (title != nil) {
+        _CGContextPushBeginDraw(context);
+        auto popEnd = wil::ScopeExit([context]() { _CGContextPopEndDraw(context); });
+
         CGSize size;
         id font = [UIFont defaultFont];
         size = [title sizeWithFont:font constrainedToSize:CGSizeMake(0.0f, 0.0f) lineBreakMode:UILineBreakModeClip];
@@ -127,9 +132,9 @@ - (void)drawRect:(CGRect)pos {
         textRect.size.width = rect.size.width;
         textRect.size.height = size.height;
         // TODO(DH)
-        //EbrCenterTextInRectVertically(&textRect, &size, font);
+        // EbrCenterTextInRectVertically(&textRect, &size, font);
 
-        CGContextSetFillColorWithColor(UIGraphicsGetCurrentContext(), (CGColorRef)[UIColor whiteColor]);
+        CGContextSetFillColorWithColor(context, (CGColorRef)[UIColor whiteColor]);
         size = [title drawInRect:textRect withFont:font lineBreakMode:UILineBreakModeClip alignment:UITextAlignmentCenter];
     }
 }

Frameworks/UIKit/UITextView.mm

@@ -398,7 +398,11 @@ - (void)setSpellCheckingType:(UITextSpellCheckingType)spellType {
  @Status Interoperable
 */
 - (void)drawRect:(CGRect)rect {
-    CGContextSetFillColorWithColor(UIGraphicsGetCurrentContext(), [_textColor CGColor]);
+    CGContextRef ctx = UIGraphicsGetCurrentContext();
+    _CGContextPushBeginDraw(ctx);
+    auto popEnd = wil::ScopeExit([ctx]() { _CGContextPopEndDraw(ctx); });
+
+    CGContextSetFillColorWithColor(ctx, [_textColor CGColor]);
 
     NSRange range{ 0, INT_MAX };
     CGPoint origin = self.bounds.origin;
@@ -759,7 +763,7 @@ - (CGSize)sizeThatFits:(CGSize)fitSize {
     centerRect.origin.y = 0;
     centerRect.size = fontExtent;
     // TODO(DH)
-    //EbrCenterTextInRectVertically(&centerRect, &fontExtent, _font);
+    // EbrCenterTextInRectVertically(&centerRect, &fontExtent, _font);
     rect.origin.y += centerRect.origin.y;
 
     ret.width = ourRect.size.width;

Frameworks/UIKit/UIView.mm

@@ -41,6 +41,7 @@
 #import "UIGestureRecognizerInternal.h"
 #import "CALayerInternal.h"
 #import "CAAnimationInternal.h"
+#import "CGContextInternal.h"
 #import <AutoLayout.h>
 #import <NSLayoutConstraint+AutoLayout.h>
 #import "NSLayoutAnchorInternal.h"
@@ -243,7 +244,7 @@ - (bool)_processGesturesForTouch:(UITouch*)touch event:(UIEvent*)event touchEven
     // scanning DManip Gestures, if one gesture is ongoing, cancel all DManip Gestures
     // otherwise, send Touch to DManip gestures
     for (int i = 0; i < dManipGestureCount; i++) {
-         UIGestureRecognizer* dManipGesture = dManipRecognizers[i];
+        UIGestureRecognizer* dManipGesture = dManipRecognizers[i];
         if (gestureOnGoing) {
             [dManipGesture _cancelIfActive];
             if (DEBUG_GESTURES) {
@@ -527,9 +528,7 @@ - (UITouchPhase)_processPointerEvent:(WUXIPointerRoutedEventArgs*)pointerEventAr
     if (!touchPoint.touch->_view) {
         // Ignore if the pointer isn't captured
         if (DEBUG_TOUCHES_LIGHT) {
-            TraceVerbose(TAG,
-                L"View for touch is nil!, ignoring touch for touchPhase %d.",
-                touchPhase);
+            TraceVerbose(TAG, L"View for touch is nil!, ignoring touch for touchPhase %d.", touchPhase);
         }
     } else if (touchPhase != UITouchPhaseBegan && ![touchPoint.touch->_view->priv->currentTouches containsObject:touchPoint.touch]) {
         // Ignore if the pointer isn't captured
@@ -2252,14 +2251,18 @@ - (CGPoint)convertPoint:(CGPoint)pos fromView:(UIView*)fromView {
 */
 - (void)drawLayer:(CALayer*)layer inContext:(CGContextRef)context {
     UIGraphicsPushContext(context);
+    _CGContextPushBeginDraw(context);
+
+    auto popEnd = wil::ScopeExit([context]() {
+        _CGContextPopEndDraw(context);
+        UIGraphicsPopContext();
+    });
 
     CGRect bounds;
     // TODO(DH)
     bounds = self.bounds;
-    //bounds = CGContextGetClipBoundingBox(context);
+    // bounds = CGContextGetClipBoundingBox(context);
     [self drawRect:bounds];
-
-    UIGraphicsPopContext();
 }
 
 /**

Frameworks/include/CGContextInternal.h

@@ -41,6 +41,22 @@ COREGRAPHICS_EXPORT bool CGContextIsPointInPath(CGContextRef c, bool eoFill, flo
 COREGRAPHICS_EXPORT void CGContextDrawGlyphRun(CGContextRef ctx, const DWRITE_GLYPH_RUN* glyphRun);
 
 // Bitmap Context Internal
-COREGRAPHICS_EXPORT CGContextRef _CGBitmapContextCreateWithRenderTarget(ID2D1RenderTarget* renderTarget, CGImageRef img, WICPixelFormatGUID outputPixelFormat);
+COREGRAPHICS_EXPORT CGContextRef _CGBitmapContextCreateWithRenderTarget(ID2D1RenderTarget* renderTarget,
+                                                                        CGImageRef img,
+                                                                        WICPixelFormatGUID outputPixelFormat);
 COREGRAPHICS_EXPORT CGContextRef _CGBitmapContextCreateWithFormat(int width, int height, __CGSurfaceFormat fmt);
 COREGRAPHICS_EXPORT CGImageRef CGBitmapContextGetImage(CGContextRef ctx);
+// Reduces the number of BeginDraw() and EndDraw() calls needed, by counting in a stack-like manner,
+// and only calling BeginDraw()/EndDraw() when the stack is empty/emptied
+COREGRAPHICS_EXPORT void _CGContextPushBeginDraw(CGContextRef ctx);
+COREGRAPHICS_EXPORT void _CGContextPopEndDraw(CGContextRef ctx);
+
+// If currently in a Begin/EndDraw stack, Escape will EndDraw(), Unescape will BeginDraw()
+// For scenarios where a Begin/EndDraw pair needs to be temporarily escaped, to be returned to at a later time
+// Ie:
+//      - Switching render targets - Illegal to do so if currently in a Begin/EndDraw pair
+//      - Cairo - ID2D1RenderTarget is considered to 'own' the bitmap during Begin/EndDraw,
+//                unsafe to edit the same bitmap from cairo at this time
+// Also counts in a stack-like manner, so that the escape and unescape only happen once
+COREGRAPHICS_EXPORT void _CGContextEscapeBeginEndDrawStack(CGContextRef ctx);
+COREGRAPHICS_EXPORT void _CGContextUnescapeBeginEndDrawStack(CGContextRef ctx);

build/CoreGraphics/dll/CoreGraphics.def

@@ -242,6 +242,10 @@ LIBRARY CoreGraphics
         _CGContextCreateWithD2DRenderTarget
         _CGGetD2DFactory
         _CGGetPixelFormatProperties
+        _CGContextPushBeginDraw
+        _CGContextPopEndDraw
+        _CGContextEscapeBeginEndDrawStack
+        _CGContextUnescapeBeginEndDrawStack
 
         ; CGDataConsumer.mm
         CGDataConsumerCreate

samples/XAMLCatalog/XAMLCatalog/CustomTextControlViewController.m

@@ -874,7 +874,7 @@ - (void)viewDidLoad {
         textEdit.autoresizingMask = infoLabel.autoresizingMask = focusButton.autoresizingMask =
             UIViewAutoresizingFlexibleLeftMargin | UIViewAutoresizingFlexibleRightMargin | UIViewAutoresizingFlexibleBottomMargin;
 
-        infoLabel.text = @"Click the control to gain focus. Use the keyboard to type and caret nagivate. Hold shift to update the "
+        infoLabel.text = @"Click the control to gain focus. Use the keyboard to type and caret navigate. Hold shift to update the "
                          @"selection. Right click or Ctrl+C or V to copy and paste.";
         infoLabel.numberOfLines = 0;
         infoLabel.textAlignment = NSTextAlignmentCenter;

samples/XAMLCatalog/XAMLCatalog/XAMLCatalog.storyboard

@@ -360,7 +360,7 @@
                                     <constraint firstAttribute="height" constant="100" id="jzf-wl-pPs"/>
                                     <constraint firstAttribute="width" constant="300" id="oPb-uK-RMZ"/>
                                 </constraints>
-                                <string key="text">Click the control to gain focus. Use the keyboard to type and caret nagivate. Hold shift to update the selection. Right click or Ctrl+C or V to copy and paste.</string>
+                                <string key="text">Click the control to gain focus. Use the keyboard to type and caret navigate. Hold shift to update the selection. Right click or Ctrl+C or V to copy and paste.</string>
                                 <fontDescription key="fontDescription" type="system" pointSize="17"/>
                                 <color key="textColor" red="0.0" green="0.0" blue="0.0" alpha="1" colorSpace="calibratedRGB"/>
                                 <nil key="highlightedColor"/>