textblobblockreordering.cpp

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/*
 * Copyright 2016 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */
 
#include "gm/gm.h"
#include "include/core/SkBlendMode.h"
#include "include/core/SkCanvas.h"
#include "include/core/SkColor.h"
#include "include/core/SkFont.h"
#include "include/core/SkFontTypes.h"
#include "include/core/SkPaint.h"
#include "include/core/SkRect.h"
#include "include/core/SkRefCnt.h"
#include "include/core/SkScalar.h"
#include "include/core/SkSize.h"
#include "include/core/SkString.h"
#include "include/core/SkTextBlob.h"
#include "include/core/SkTypeface.h"
#include "tools/ToolUtils.h"
#include "tools/fonts/FontToolUtils.h"
 
#include <string.h>
 
namespace skiagm {
class TextBlobBlockReordering : public GM {
public:
    // This gm tests that textblobs translate properly when their draw order is different from their
    // flush order
    TextBlobBlockReordering() { }
 
protected:
    void onOnceBeforeDraw() override {
        SkTextBlobBuilder builder;
 
        // make textblob
        // Large text is used to trigger atlas eviction
        SkFont font(ToolUtils::DefaultPortableTypeface(), 56);
        font.setEdging(SkFont::Edging::kAlias);
        const char* text = "AB";
 
        SkRect bounds;
        font.measureText(text, strlen(text), SkTextEncoding::kUTF8, &bounds);
 
        SkScalar yOffset = bounds.height();
        ToolUtils::add_to_text_blob(&builder, text, font, 0, yOffset - 30);
 
        // build
        fBlob = builder.make();
    }
 
    SkString getName() const override { return SkString("textblobblockreordering"); }
 
    SkISize getISize() override { return SkISize::Make(kWidth, kHeight); }
 
    // This draws the same text blob 3 times.  The second draw used a different xfer mode so its
    // GrDrawOp doesn't get combined with the first and third. Ultimately, they will be flushed in
    // the order first, third, and then second.
    void onDraw(SkCanvas* canvas) override {
        canvas->drawColor(SK_ColorGRAY);
 
        SkPaint paint;
        canvas->translate(10, 40);
 
        SkRect bounds = fBlob->bounds();
        const int yDelta = SkScalarFloorToInt(bounds.height()) + 20;
        const int xDelta = SkScalarFloorToInt(bounds.width());
 
        canvas->drawTextBlob(fBlob, 0, 0, paint);
 
        canvas->translate(SkIntToScalar(xDelta), SkIntToScalar(yDelta));
 
        // Draw a rect where the text should be, and then twiddle the xfermode so we don't combine.
        SkPaint redPaint;
        redPaint.setColor(SK_ColorRED);
        canvas->drawRect(bounds, redPaint);
        SkPaint srcInPaint(paint);
        srcInPaint.setBlendMode(SkBlendMode::kSrcIn);
        canvas->drawTextBlob(fBlob, 0, 0, srcInPaint);
 
        canvas->translate(SkIntToScalar(xDelta), SkIntToScalar(yDelta));
        canvas->drawTextBlob(fBlob, 0, 0, paint);
    }
 
private:
    sk_sp<SkTextBlob> fBlob;
 
    inline static constexpr int kWidth = 275;
    inline static constexpr int kHeight = 200;
 
    using INHERITED = GM;
};
 
//////////////////////////////////////////////////////////////////////////////
 
DEF_GM(return new TextBlobBlockReordering;)
}  // namespace skiagm