unify how canvas checks for null on skia objects (images, blobs, pictures)

src/core/SkCanvas.cpp

 /*
  * Copyright 2008 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBitmapDevice.h"
 #include "SkCanvas.h"
 #include "SkCanvasPriv.h"
@@ skipping 24 matching lines @@
 #include "SkTraceEvent.h"
 
 #include <new>
 
 #if SK_SUPPORT_GPU
 #include "GrContext.h"
 #include "GrRenderTarget.h"
 #include "SkGr.h"
 #endif
 
+#define RETURN_ON_NULL(ptr)     do { if (nullptr == (ptr)) return; } while (0)
+
 /*
  *  Return true if the drawing this rect would hit every pixels in the canvas.
  *
  *  Returns false if
  *  - rect does not contain the canvas' bounds
  *  - paint is not fill
  *  - paint would blur or otherwise change the coverage of the rect
  */
 bool SkCanvas::wouldOverwriteEntireSurface(const SkRect* rect, const SkPaint* paint,
                                            ShaderOverrideOpacity overrideOpacity) const {
@@ skipping 1867 matching lines @@
                             const uint16_t indices[], int indexCount, const SkPaint& paint) {
     this->onDrawVertices(vmode, vertexCount, vertices, texs, colors, xmode,
                          indices, indexCount, paint);
 }
 
 void SkCanvas::drawPath(const SkPath& path, const SkPaint& paint) {
     this->onDrawPath(path, paint);
 }
 
 void SkCanvas::drawImage(const SkImage* image, SkScalar x, SkScalar y, const SkPaint* paint) {
+    RETURN_ON_NULL(image);
     this->onDrawImage(image, x, y, paint);
 }
 
 void SkCanvas::drawImageRect(const SkImage* image, const SkRect& src, const SkRect& dst,
                              const SkPaint* paint, SrcRectConstraint constraint) {
+    RETURN_ON_NULL(image);
     if (dst.isEmpty() || src.isEmpty()) {
         return;
     }
     this->onDrawImageRect(image, &src, dst, paint, constraint);
 }
 
 void SkCanvas::drawImageRect(const SkImage* image, const SkIRect& isrc, const SkRect& dst,
                              const SkPaint* paint, SrcRectConstraint constraint) {
+    RETURN_ON_NULL(image);
     this->drawImageRect(image, SkRect::Make(isrc), dst, paint, constraint);
 }
 
 void SkCanvas::drawImageRect(const SkImage* image, const SkRect& dst, const SkPaint* paint,
                              SrcRectConstraint constraint) {
+    RETURN_ON_NULL(image);
     this->drawImageRect(image, SkRect::MakeIWH(image->width(), image->height()), dst, paint,
                         constraint);
 }
 
 void SkCanvas::drawImageNine(const SkImage* image, const SkIRect& center, const SkRect& dst,
                              const SkPaint* paint) {
+    RETURN_ON_NULL(image);
     if (dst.isEmpty()) {
         return;
     }
     if (!SkNinePatchIter::Valid(image->width(), image->height(), center)) {
         this->drawImageRect(image, dst, paint);
     }
     this->onDrawImageNine(image, center, dst, paint);
 }
 
 void SkCanvas::drawBitmap(const SkBitmap& bitmap, SkScalar dx, SkScalar dy, const SkPaint* paint) {
@@ skipping 29 matching lines @@
     }
     if (!SkNinePatchIter::Valid(bitmap.width(), bitmap.height(), center)) {
         this->drawBitmapRect(bitmap, dst, paint);
     }
     this->onDrawBitmapNine(bitmap, center, dst, paint);
 }
 
 void SkCanvas::drawAtlas(const SkImage* atlas, const SkRSXform xform[], const SkRect tex[],
                          const SkColor colors[], int count, SkXfermode::Mode mode,
                          const SkRect* cull, const SkPaint* paint) {
+    RETURN_ON_NULL(atlas);
     if (count <= 0) {
         return;
     }
     SkASSERT(atlas);
     SkASSERT(xform);
     SkASSERT(tex);
     this->onDrawAtlas(atlas, xform, tex, colors, count, mode, cull, paint);
 }
 
 void SkCanvas::legacy_drawImageRect(const SkImage* image, const SkRect* src, const SkRect& dst,
@@ skipping 622 matching lines @@
     TRACE_EVENT0("disabled-by-default-skia", "SkCanvas::drawPosTextH()");
     this->onDrawPosTextH(text, byteLength, xpos, constY, paint);
 }
 void SkCanvas::drawTextOnPath(const void* text, size_t byteLength, const SkPath& path,
                               const SkMatrix* matrix, const SkPaint& paint) {
     TRACE_EVENT0("disabled-by-default-skia", "SkCanvas::drawTextOnPath()");
     this->onDrawTextOnPath(text, byteLength, path, matrix, paint);
 }
 void SkCanvas::drawTextBlob(const SkTextBlob* blob, SkScalar x, SkScalar y,
                             const SkPaint& paint) {
+    RETURN_ON_NULL(blob);
     TRACE_EVENT0("disabled-by-default-skia", "SkCanvas::drawTextBlob()");
-    if (blob) {
-        this->onDrawTextBlob(blob, x, y, paint);
-    }
+    this->onDrawTextBlob(blob, x, y, paint);
 }
 
 void SkCanvas::onDrawVertices(VertexMode vmode, int vertexCount,
                               const SkPoint verts[], const SkPoint texs[],
                               const SkColor colors[], SkXfermode* xmode,
                               const uint16_t indices[], int indexCount,
                               const SkPaint& paint) {
     TRACE_EVENT0("disabled-by-default-skia", "SkCanvas::drawVertices()");
     LOOPER_BEGIN(paint, SkDrawFilter::kPath_Type, nullptr)
 
@@ skipping 30 matching lines @@
     LOOPER_BEGIN(paint, SkDrawFilter::kPath_Type, nullptr)
 
     while (iter.next()) {
         iter.fDevice->drawPatch(iter, cubics, colors, texCoords, xmode, paint);
     }
 
     LOOPER_END
 }
 
 void SkCanvas::drawDrawable(SkDrawable* dr, SkScalar x, SkScalar y) {
-    if (dr) {
-        if (x || y) {
-            SkMatrix matrix = SkMatrix::MakeTrans(x, y);
-            this->onDrawDrawable(dr, &matrix);
-        } else {
-            this->onDrawDrawable(dr, nullptr);
-        }
+    RETURN_ON_NULL(dr);
+    if (x || y) {
+        SkMatrix matrix = SkMatrix::MakeTrans(x, y);
+        this->onDrawDrawable(dr, &matrix);
+    } else {
+        this->onDrawDrawable(dr, nullptr);
     }
 }
 
 void SkCanvas::drawDrawable(SkDrawable* dr, const SkMatrix* matrix) {
-    if (dr) {
-        if (matrix && matrix->isIdentity()) {
-            matrix = nullptr;
-        }
-        this->onDrawDrawable(dr, matrix);
+    RETURN_ON_NULL(dr);
+    if (matrix && matrix->isIdentity()) {
+        matrix = nullptr;
     }
+    this->onDrawDrawable(dr, matrix);
 }
 
 void SkCanvas::onDrawDrawable(SkDrawable* dr, const SkMatrix* matrix) {
     SkRect bounds = dr->getBounds();
     if (matrix) {
         matrix->mapRect(&bounds);
     }
     if (this->quickReject(bounds)) {
         return;
     }
@@ skipping 149 matching lines @@
 /**
  *  This constant is trying to balance the speed of ref'ing a subpicture into a parent picture,
  *  against the playback cost of recursing into the subpicture to get at its actual ops.
  *
  *  For now we pick a conservatively small value, though measurement (and other heuristics like
  *  the type of ops contained) may justify changing this value.
  */
 #define kMaxPictureOpsToUnrollInsteadOfRef  1
 
 void SkCanvas::drawPicture(const SkPicture* picture, const SkMatrix* matrix, const SkPaint* paint) {
+    RETURN_ON_NULL(picture);
+
     TRACE_EVENT0("disabled-by-default-skia", "SkCanvas::drawPicture()");
-    if (picture) {
-        if (matrix && matrix->isIdentity()) {
-            matrix = nullptr;
-        }
-        if (picture->approximateOpCount() <= kMaxPictureOpsToUnrollInsteadOfRef) {
-            SkAutoCanvasMatrixPaint acmp(this, matrix, paint, picture->cullRect());
-            picture->playback(this);
-        } else {
-            this->onDrawPicture(picture, matrix, paint);
-        }
+    if (matrix && matrix->isIdentity()) {
+        matrix = nullptr;
+    }
+    if (picture->approximateOpCount() <= kMaxPictureOpsToUnrollInsteadOfRef) {
+        SkAutoCanvasMatrixPaint acmp(this, matrix, paint, picture->cullRect());
+        picture->playback(this);
+    } else {
+        this->onDrawPicture(picture, matrix, paint);
     }
 }
 
 void SkCanvas::onDrawPicture(const SkPicture* picture, const SkMatrix* matrix,
                              const SkPaint* paint) {
     if (!paint || paint->canComputeFastBounds()) {
         SkRect bounds = picture->cullRect();
         if (paint) {
             paint->computeFastBounds(bounds, &bounds);
         }
@@ skipping 115 matching lines @@
     }
 
     if (matrix) {
         canvas->concat(*matrix);
     }
 }
 
 SkAutoCanvasMatrixPaint::~SkAutoCanvasMatrixPaint() {
     fCanvas->restoreToCount(fSaveCount);
 }