don't rely on canvas->readPixels

Bug: skia:3216
Change-Id: I01a8d0083c79c0fe71fbc4d8cfdde4fa6e48b636
Reviewed-on: https://skia-review.googlesource.com/25741
Commit-Queue: Mike Reed <reed@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>

1 files changed, 10 insertions, 14 deletions

diff --git a/tests/ImageFilterTest.cpp b/tests/ImageFilterTest.cpp
index 69b31f184c..93389b3db2 100644
--- a/tests/ImageFilterTest.cpp
+++ b/tests/ImageFilterTest.cpp
@@ -1413,7 +1413,8 @@ DEF_TEST(ImageFilterMatrixConvolutionSanityTest, reporter) {
     REPORTER_ASSERT(reporter, nullptr == conv.get());
 }
 
-static void test_xfermode_cropped_input(SkCanvas* canvas, skiatest::Reporter* reporter) {
+static void test_xfermode_cropped_input(SkSurface* surf, skiatest::Reporter* reporter) {
+    auto canvas = surf->getCanvas();
     canvas->clear(0);
 
     SkBitmap bitmap;
@@ -1442,17 +1443,17 @@ static void test_xfermode_cropped_input(SkCanvas* canvas, skiatest::Reporter* re
 
     uint32_t pixel;
     SkImageInfo info = SkImageInfo::Make(1, 1, kBGRA_8888_SkColorType, kUnpremul_SkAlphaType);
-    canvas->readPixels(info, &pixel, 4, 0, 0);
+    surf->readPixels(info, &pixel, 4, 0, 0);
     REPORTER_ASSERT(reporter, pixel == SK_ColorGREEN);
 
     paint.setImageFilter(std::move(xfermodeNoBg));
     canvas->drawBitmap(bitmap, 0, 0, &paint);   // drawSprite
-    canvas->readPixels(info, &pixel, 4, 0, 0);
+    surf->readPixels(info, &pixel, 4, 0, 0);
     REPORTER_ASSERT(reporter, pixel == SK_ColorGREEN);
 
     paint.setImageFilter(std::move(xfermodeNoFgNoBg));
     canvas->drawBitmap(bitmap, 0, 0, &paint);   // drawSprite
-    canvas->readPixels(info, &pixel, 4, 0, 0);
+    surf->readPixels(info, &pixel, 4, 0, 0);
     REPORTER_ASSERT(reporter, pixel == SK_ColorGREEN);
 }
 
@@ -1491,26 +1492,23 @@ DEF_TEST(ImageFilterNestedSaveLayer, reporter) {
 
     SkImageInfo info = SkImageInfo::Make(1, 1, kBGRA_8888_SkColorType, kUnpremul_SkAlphaType);
     uint32_t pixel;
-    canvas.readPixels(info, &pixel, 4, 25, 25);
+    temp.readPixels(info, &pixel, 4, 25, 25);
     REPORTER_ASSERT(reporter, pixel == SK_ColorGREEN);
 
     // Test that drawSprite() with a filter nested inside a saveLayer() applies the
     // correct offset to the filter matrix.
     canvas.clear(0x0);
-    canvas.readPixels(info, &pixel, 4, 25, 25);
+    temp.readPixels(info, &pixel, 4, 25, 25);
     canvas.saveLayer(&bounds1, nullptr);
     canvas.drawBitmap(bitmap, 20, 20, &filterPaint);    // drawSprite
     canvas.restore();
 
-    canvas.readPixels(info, &pixel, 4, 25, 25);
+    temp.readPixels(info, &pixel, 4, 25, 25);
     REPORTER_ASSERT(reporter, pixel == SK_ColorGREEN);
 }
 
 DEF_TEST(XfermodeImageFilterCroppedInput, reporter) {
-    SkBitmap temp;
-    temp.allocN32Pixels(100, 100);
-    SkCanvas canvas(temp);
-    test_xfermode_cropped_input(&canvas, reporter);
+    test_xfermode_cropped_input(SkSurface::MakeRasterN32Premul(100, 100).get(), reporter);
 }
 
 static void test_composed_imagefilter_offset(skiatest::Reporter* reporter, GrContext* context) {
@@ -1834,9 +1832,7 @@ DEF_GPUTEST_FOR_RENDERING_CONTEXTS(XfermodeImageFilterCroppedInput_Gpu, reporter
             SkBudgeted::kNo,
             SkImageInfo::Make(1, 1, kRGBA_8888_SkColorType, kPremul_SkAlphaType)));
 
-    SkCanvas* canvas = surf->getCanvas();
-
-    test_xfermode_cropped_input(canvas, reporter);
+    test_xfermode_cropped_input(surf.get(), reporter);
 }
 
 DEF_GPUTEST_FOR_ALL_CONTEXTS(ImageFilterBlurLargeImage_Gpu, reporter, ctxInfo) {