Enhance SkDropShadowImageFilter to support separate X & Y sigmas, and crop rect. This required a new flavour of the constructor.

This is driven by the feDropShadow filter effect in SVG, which unlike the shorthand version accepts separate X & Y sigmas.

Covered by new GM dropshadowimagefilter.

R=reed@google.com

Review URL: https://codereview.chromium.org/88243004

git-svn-id: http://skia.googlecode.com/svn/trunk@12401 2bbb7eff-a529-9590-31e7-b0007b416f81

1 files changed, 174 insertions, 0 deletions

diff --git a/gm/dropshadowimagefilter.cpp b/gm/dropshadowimagefilter.cpp
new file mode 100644
index 0000000000..6cffd5bb4a
--- /dev/null
+++ b/gm/dropshadowimagefilter.cpp
@@ -0,0 +1,174 @@
+/*
+ * Copyright 2013 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "gm.h"
+#include "SkColorFilter.h"
+
+#include "SkColorFilterImageFilter.h"
+#include "SkDropShadowImageFilter.h"
+
+///////////////////////////////////////////////////////////////////////////////
+
+static void draw_paint(SkCanvas* canvas, const SkRect& r, SkImageFilter* imf) {
+    SkPaint paint;
+    paint.setImageFilter(imf);
+    paint.setColor(SK_ColorBLACK);
+    canvas->save();
+    canvas->clipRect(r);
+    canvas->drawPaint(paint);
+    canvas->restore();
+}
+
+static void draw_path(SkCanvas* canvas, const SkRect& r, SkImageFilter* imf) {
+    SkPaint paint;
+    paint.setColor(SK_ColorGREEN);
+    paint.setImageFilter(imf);
+    paint.setAntiAlias(true);
+    canvas->save();
+    canvas->clipRect(r);
+    canvas->drawCircle(r.centerX(), r.centerY(), r.width()/3, paint);
+    canvas->restore();
+}
+
+static void draw_text(SkCanvas* canvas, const SkRect& r, SkImageFilter* imf) {
+    SkPaint paint;
+    paint.setImageFilter(imf);
+    paint.setColor(SK_ColorGREEN);
+    paint.setAntiAlias(true);
+    paint.setTextSize(r.height()/2);
+    paint.setTextAlign(SkPaint::kCenter_Align);
+    canvas->save();
+    canvas->clipRect(r);
+    canvas->drawText("Text", 4, r.centerX(), r.centerY(), paint);
+    canvas->restore();
+}
+
+static void draw_bitmap(SkCanvas* canvas, const SkRect& r, SkImageFilter* imf) {
+    SkPaint paint;
+
+    SkIRect bounds;
+    r.roundOut(&bounds);
+
+    SkBitmap bm;
+    bm.setConfig(SkBitmap::kARGB_8888_Config, bounds.width(), bounds.height());
+    bm.allocPixels();
+    bm.eraseColor(SK_ColorTRANSPARENT);
+    SkCanvas c(bm);
+    draw_path(&c, r, NULL);
+
+    paint.setImageFilter(imf);
+    canvas->save();
+    canvas->clipRect(r);
+    canvas->drawBitmap(bm, 0, 0, &paint);
+    canvas->restore();
+}
+
+static void draw_sprite(SkCanvas* canvas, const SkRect& r, SkImageFilter* imf) {
+    SkPaint paint;
+
+    SkIRect bounds;
+    r.roundOut(&bounds);
+
+    SkBitmap bm;
+    bm.setConfig(SkBitmap::kARGB_8888_Config, bounds.width(), bounds.height());
+    bm.allocPixels();
+    bm.eraseColor(SK_ColorRED);
+    SkCanvas c(bm);
+
+    SkIRect cropRect = SkIRect::MakeXYWH(10, 10, 44, 44);
+    paint.setColor(SK_ColorGREEN);
+    c.drawRect(SkRect::Make(cropRect), paint);
+
+    paint.setImageFilter(imf);
+    SkPoint loc = { r.fLeft, r.fTop };
+    canvas->getTotalMatrix().mapPoints(&loc, 1);
+    canvas->drawSprite(bm,
+                       SkScalarRoundToInt(loc.fX), SkScalarRoundToInt(loc.fY),
+                       &paint);
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
+class DropShadowImageFilterGM : public skiagm::GM {
+public:
+    DropShadowImageFilterGM () {}
+
+protected:
+
+    virtual SkString onShortName() {
+        return SkString("dropshadowimagefilter");
+    }
+
+    virtual SkISize onISize() { return SkISize::Make(400, 700); }
+
+    void draw_frame(SkCanvas* canvas, const SkRect& r) {
+        SkPaint paint;
+        paint.setStyle(SkPaint::kStroke_Style);
+        paint.setColor(SK_ColorRED);
+        canvas->drawRect(r, paint);
+    }
+
+    virtual uint32_t onGetFlags() const {
+        // Because of the use of drawSprite, this test is excluded
+        // from scaled replay tests because drawSprite ignores the
+        // reciprocal scale that is applied at record time, which is
+        // the intended behavior of drawSprite.
+        return kSkipScaledReplay_Flag;
+    }
+
+    virtual void onDraw(SkCanvas* canvas) {
+        void (*drawProc[])(SkCanvas*, const SkRect&, SkImageFilter*) = {
+            draw_sprite, draw_bitmap, draw_path, draw_paint, draw_text
+        };
+
+        SkAutoTUnref<SkColorFilter> cf(
+            SkColorFilter::CreateModeFilter(SK_ColorMAGENTA, SkXfermode::kSrcIn_Mode));
+        SkAutoTUnref<SkImageFilter> cfif(SkColorFilterImageFilter::Create(cf.get()));
+        SkImageFilter::CropRect cropRect(SkRect::Make(SkIRect::MakeXYWH(10, 10, 44, 44)),
+                                         SkImageFilter::CropRect::kHasAll_CropEdge);
+        SkImageFilter::CropRect bogusRect(SkRect::Make(SkIRect::MakeXYWH(-100, -100, 10, 10)),
+                                          SkImageFilter::CropRect::kHasAll_CropEdge);
+
+        SkImageFilter* filters[] = {
+            NULL,
+            new SkDropShadowImageFilter(7.0f, 0.0f, 0.0f, 3.0f, SK_ColorBLUE),
+            new SkDropShadowImageFilter(0.0f, 7.0f, 3.0f, 0.0f, SK_ColorBLUE),
+            new SkDropShadowImageFilter(7.0f, 7.0f, 3.0f, 3.0f, SK_ColorBLUE),
+            new SkDropShadowImageFilter(7.0f, 7.0f, 3.0f, 3.0f, SK_ColorBLUE, cfif),
+            new SkDropShadowImageFilter(7.0f, 7.0f, 3.0f, 3.0f, SK_ColorBLUE, NULL, &cropRect),
+            new SkDropShadowImageFilter(7.0f, 7.0f, 3.0f, 3.0f, SK_ColorBLUE, NULL, &bogusRect),
+        };
+
+        SkRect r = SkRect::MakeWH(SkIntToScalar(64), SkIntToScalar(64));
+        SkScalar MARGIN = SkIntToScalar(16);
+        SkScalar DX = r.width() + MARGIN;
+        SkScalar DY = r.height() + MARGIN;
+
+        canvas->translate(MARGIN, MARGIN);
+        for (size_t j = 0; j < SK_ARRAY_COUNT(drawProc); ++j) {
+            canvas->save();
+            for (size_t i = 0; i < SK_ARRAY_COUNT(filters); ++i) {
+                drawProc[j](canvas, r, filters[i]);
+                canvas->translate(0, DY);
+            }
+            canvas->restore();
+            canvas->translate(DX, 0);
+        }
+
+        for(size_t j = 0; j < SK_ARRAY_COUNT(filters); ++j) {
+            SkSafeUnref(filters[j]);
+        }
+    }
+
+private:
+    typedef GM INHERITED;
+};
+
+///////////////////////////////////////////////////////////////////////////////
+
+static skiagm::GM* MyFactory(void*) { return new DropShadowImageFilterGM; }
+static skiagm::GMRegistry reg(MyFactory);