SkPDF: scale entire canvas for non-standard rasterDpi

TODO: add better testing around this.

BUG: chromium:481429

Change-Id: I1296fae3fc9775febf17bba75722c30f48d67a95
Reviewed-on: https://skia-review.googlesource.com/127051
Commit-Queue: Hal Canary <halcanary@google.com>
Reviewed-by: Florin Malita <fmalita@chromium.org>

1 files changed, 3 insertions, 9 deletions

diff --git a/src/pdf/SkPDFDevice.cpp b/src/pdf/SkPDFDevice.cpp
index c18219ab0d..ced94ce9a9 100644
--- a/src/pdf/SkPDFDevice.cpp
+++ b/src/pdf/SkPDFDevice.cpp
@@ -508,8 +508,9 @@ void SkPDFDevice::setFlip() {
     // natively has the origin at the bottom left. This matrix
     // corrects for that.  But that only needs to be done once, we
     // don't do it when layering.
-    fInitialTransform.setTranslate(0, SkIntToScalar(fPageSize.fHeight));
-    fInitialTransform.preScale(SK_Scalar1, -SK_Scalar1);
+    SkScalar rasterScale = SkPDFUtils::kDpiForRasterScaleOne / fDocument->rasterDpi();
+    fInitialTransform.setConcat(SkMatrix::MakeScale(rasterScale, -rasterScale),
+                                SkMatrix::MakeTrans(0, -fPageSize.fHeight));
 }
 
 SkPDFDevice::~SkPDFDevice() {
@@ -797,9 +798,6 @@ void SkPDFDevice::internalDrawPathWithFilter(const SkClipStack& clipStack,
                                      : SkStrokeRec::kHairline_InitStyle;
     path.transform(ctm, &path);
 
-    // TODO(halcanary): respect fDocument->rasterDpi().
-    //        SkScalar rasterScale = (float)rasterDpi / SkPDFUtils::kDpiForRasterScaleOne;
-    // Would it be easier to just change the device size (and pre-scale the canvas)?
     SkIRect bounds = clipStack.bounds(this->bounds()).roundOut();
     SkMask sourceMask;
     if (!SkDraw::DrawToMask(path, &bounds, paint->getMaskFilter(), &SkMatrix::I(),
@@ -2157,7 +2155,6 @@ void SkPDFDevice::internalDrawImageRect(SkKeyedImage imageSubset,
 
     // Rasterize the bitmap using perspective in a new bitmap.
     if (transform.hasPerspective()) {
-        SkASSERT(fDocument->rasterDpi() > 0);
         // Transform the bitmap in the new space, without taking into
         // account the initial transform.
         SkPath perspectiveOutline;
@@ -2173,9 +2170,6 @@ void SkPDFDevice::internalDrawImageRect(SkKeyedImage imageSubset,
         // account the initial transform.
         SkMatrix total = transform;
         total.postConcat(fInitialTransform);
-        SkScalar dpiScale = SkIntToScalar(fDocument->rasterDpi()) /
-                            SkIntToScalar(SkPDFUtils::kDpiForRasterScaleOne);
-        total.postScale(dpiScale, dpiScale);
 
         SkPath physicalPerspectiveOutline;
         physicalPerspectiveOutline.addRect(imageBounds);