Add GM to test drawing atlas case

gm/drawminibitmaprect.cpp

Index: gm/drawminibitmaprect.cpp
diff --git a/gm/drawminibitmaprect.cpp b/gm/drawminibitmaprect.cpp
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index 0000000000000000000000000000000000000000..7617aa5fdf72271b475d0722fb33433dddf67d2f
--- /dev/null
+++ b/gm/drawminibitmaprect.cpp
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+/*

[robertphillips, 2015/08/13 18:17:52]

2015 ?

[joshualitt, 2015/08/13 19:31:27]

Acknowledged.

+ * Copyright 2011 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"

[robertphillips, 2015/08/13 18:17:51]

Do we need the blur headers ?

[joshualitt, 2015/08/13 19:31:27]

Acknowledged.

+#include "SkBlurMask.h"
+#include "SkBlurMaskFilter.h"
+#include "SkColorPriv.h"
+#include "SkGradientShader.h"
+#include "SkShader.h"
+#include "SkImage.h"
+#include "SkRandom.h"
+
+static SkImage* image_from_bitmap(const SkBitmap& bm) {
+    SkBitmap b(bm);
+    b.lockPixels();
+    return SkImage::NewRasterCopy(b.info(), b.getPixels(), b.rowBytes());
+}
+

[robertphillips, 2015/08/13 18:17:52]

Can we pass the GM's canvas in here and use newSurface and newImageSnapshot?
This would be similar to the pattern used in the drawatlas GM.

+static SkImage* makebm(SkBitmap* bm, int w, int h) {
+    bm->allocN32Pixels(w, h);
+    bm->eraseColor(SK_ColorTRANSPARENT);
+
+    SkCanvas    canvas(*bm);
+
+    SkScalar wScalar = SkIntToScalar(w);
+    SkScalar hScalar = SkIntToScalar(h);
+

[robertphillips, 2015/08/13 18:17:52]

const ?

[joshualitt, 2015/08/13 19:31:27]

Acknowledged.

+    SkPoint     pt = { wScalar / 2, hScalar / 2 };
+

[robertphillips, 2015/08/13 18:17:52]

const ?

[joshualitt, 2015/08/13 19:31:27]

Acknowledged.

+    SkScalar    radius = 4 * SkMaxScalar(wScalar, hScalar);
+

[robertphillips, 2015/08/13 18:17:52]

const ?
static ?

[joshualitt, 2015/08/13 19:31:27]

Acknowledged.

+    SkColor     colors[] = { SK_ColorRED, SK_ColorYELLOW,
+                             SK_ColorGREEN, SK_ColorMAGENTA,
+                             SK_ColorBLUE, SK_ColorCYAN,
+                             SK_ColorRED};
+

[robertphillips, 2015/08/13 18:17:52]

const ?
static ?

[joshualitt, 2015/08/13 19:31:27]

Acknowledged.

+    SkScalar    pos[] = {0,
+                         SK_Scalar1 / 6,
+                         2 * SK_Scalar1 / 6,
+                         3 * SK_Scalar1 / 6,
+                         4 * SK_Scalar1 / 6,
+                         5 * SK_Scalar1 / 6,
+                         SK_Scalar1};
+

[robertphillips, 2015/08/13 18:17:51]

SkASSERT(SK_ARRAY_COUNT(colors) == SK_ARRAY_COUNT(pos)); ?
Maybe a static assert ?

[joshualitt, 2015/08/13 19:31:27]

Acknowledged.

+    SkPaint     paint;
+    SkRect rect = SkRect::MakeWH(wScalar, hScalar);
+    SkMatrix mat = SkMatrix::I();
+    for (int i = 0; i < 4; ++i) {
+        paint.setShader(SkGradientShader::CreateRadial(
+                        pt, radius,
+                        colors, pos,
+                        SK_ARRAY_COUNT(colors),
+                        SkShader::kRepeat_TileMode,
+                        0, &mat))->unref();
+        canvas.drawRect(rect, paint);
+        rect.inset(wScalar / 8, hScalar / 8);
+        mat.postScale(SK_Scalar1 / 4, SK_Scalar1 / 4);
+    }
+    // Let backends know we won't change this, so they don't have to deep copy it defensively.
+    bm->setImmutable();
+
+    return image_from_bitmap(*bm);
+}
+
+static const int gSize = 1024;
+static const int gBmpSize = 2048;
+

[robertphillips, 2015/08/13 18:17:52]

// This GM calls drawImageRect several times using the same texture. This is
intended to exercise batching of these calls.
?

[joshualitt, 2015/08/13 19:31:27]

Acknowledged.

+class DrawMiniBitmapRectGM : public skiagm::GM {
+public:
+    DrawMiniBitmapRectGM(bool antiAlias) : fAA(antiAlias) {
+        fName.set("drawminibitmaprect");
+        if (fAA) {
+            fName.appendf("_aa");
+        }
+    }
+
+    bool                  fAA;

[robertphillips, 2015/08/13 18:17:52]

Do we need to keep fLargeBitmap around?

[joshualitt, 2015/08/13 19:31:27]

Acknowledged.

+    SkBitmap              fLargeBitmap;
+    SkAutoTUnref<SkImage> fImage;
+    SkString              fName;
+
+protected:
+    SkString onShortName() override { return fName; }
+
+    SkISize onISize() override { return SkISize::Make(gSize, gSize); }
+
+    void onOnceBeforeDraw() override {
+        fImage.reset(makebm(&fLargeBitmap, gBmpSize, gBmpSize));
+    }
+
+    void onDraw(SkCanvas* canvas) override {

[robertphillips, 2015/08/13 18:17:52]

const ?

[joshualitt, 2015/08/13 19:31:27]

Acknowledged.

+        SkRect dstRect = { 0, 0, SkIntToScalar(64), SkIntToScalar(64)};
+        static const int kMaxSrcRectSize = 1 << (SkNextLog2(gBmpSize) + 2);
+
+        static const int kPadX = 30;
+        static const int kPadY = 40;
+
+        int rowCount = 0;
+        canvas->translate(SkIntToScalar(kPadX), SkIntToScalar(kPadY));

[robertphillips, 2015/08/13 18:17:52]

Is there a restore to match this ?

[joshualitt, 2015/08/13 19:31:27]

Acknowledged.

+        canvas->save();
+        SkRandom random;
+
+        SkPaint paint;
+        paint.setAntiAlias(fAA);
+        for (int w = 1; w <= kMaxSrcRectSize; w *= 3) {
+            for (int h = 1; h <= kMaxSrcRectSize; h *= 3) {
+

[robertphillips, 2015/08/13 18:17:52]

const ?

[joshualitt, 2015/08/13 19:31:27]

Acknowledged.

+                SkIRect srcRect = SkIRect::MakeXYWH((gBmpSize - w) / 2, (gBmpSize - h) / 2, w, h);
+                canvas->save();
+                switch (random.nextU() % 3) {
+                    case 0:
+                        canvas->rotate(random.nextF() * 10.f);
+                        break;
+                    case 1:
+                        canvas->rotate(-random.nextF() * 10.f);
+                        break;
+                    case 2:
+                        // rect stays rect
+                        break;
+                }
+                canvas->drawImageRect(fImage, srcRect, dstRect, &paint,
+                                      SkCanvas::kFast_SrcRectConstraint);
+                canvas->restore();
+
+                canvas->translate(dstRect.width() + SK_Scalar1 * kPadX, 0);
+                ++rowCount;
+                if ((dstRect.width() + 2 * kPadX) * rowCount > gSize) {
+                    canvas->restore();
+                    canvas->translate(0, dstRect.height() + SK_Scalar1 * kPadY);
+                    canvas->save();
+                    rowCount = 0;
+                }
+            }
+        }
+
+    }
+
+private:
+    typedef skiagm::GM INHERITED;
+};
+
+DEF_GM( return new DrawMiniBitmapRectGM(true); )
+DEF_GM( return new DrawMiniBitmapRectGM(false); )
+