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/*
* 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 "SampleCode.h"
#include "SkView.h"
#include "SkCanvas.h"
#include "SkGradientShader.h"
static void makebm(SkBitmap* bm, int w, int h) {
bm->allocN32Pixels(w, h);
bm->eraseColor(SK_ColorTRANSPARENT);
SkCanvas canvas(*bm);
SkScalar s = SkIntToScalar(w < h ? w : h);
SkPoint pts[] = { { 0, 0 }, { s, s } };
SkColor colors[] = { SK_ColorRED, SK_ColorGREEN, SK_ColorBLUE };
SkScalar pos[] = { 0, SK_Scalar1/2, SK_Scalar1 };
SkPaint paint;
paint.setDither(true);
paint.setShader(SkGradientShader::CreateLinear(pts, colors, pos,
SK_ARRAY_COUNT(colors), SkShader::kClamp_TileMode))->unref();
canvas.drawPaint(paint);
}
static SkShader* MakeBitmapShader(SkShader::TileMode tx, SkShader::TileMode ty,
int w, int h) {
static SkBitmap bmp;
if (bmp.isNull()) {
makebm(&bmp, w/2, h/4);
}
return SkShader::CreateBitmapShader(bmp, tx, ty);
}
///////////////////////////////////////////////////////////////////////////////
struct GradData {
int fCount;
const SkColor* fColors;
const SkScalar* fPos;
};
static const SkColor gColors[] = {
SK_ColorRED, SK_ColorGREEN, SK_ColorBLUE, SK_ColorWHITE, SK_ColorBLACK
};
static const GradData gGradData[] = {
{ 2, gColors, NULL },
{ 5, gColors, NULL },
};
static SkShader* MakeLinear(const SkPoint pts[2], const GradData& data, SkShader::TileMode tm) {
return SkGradientShader::CreateLinear(pts, data.fColors, data.fPos, data.fCount, tm);
}
static SkShader* MakeRadial(const SkPoint pts[2], const GradData& data, SkShader::TileMode tm) {
SkPoint center;
center.set(SkScalarAve(pts[0].fX, pts[1].fX),
SkScalarAve(pts[0].fY, pts[1].fY));
return SkGradientShader::CreateRadial(center, center.fX, data.fColors,
data.fPos, data.fCount, tm);
}
static SkShader* MakeSweep(const SkPoint pts[2], const GradData& data, SkShader::TileMode tm) {
SkPoint center;
center.set(SkScalarAve(pts[0].fX, pts[1].fX),
SkScalarAve(pts[0].fY, pts[1].fY));
return SkGradientShader::CreateSweep(center.fX, center.fY, data.fColors, data.fPos, data.fCount);
}
static SkShader* Make2Radial(const SkPoint pts[2], const GradData& data, SkShader::TileMode tm) {
SkPoint center0, center1;
center0.set(SkScalarAve(pts[0].fX, pts[1].fX),
SkScalarAve(pts[0].fY, pts[1].fY));
center1.set(SkScalarInterp(pts[0].fX, pts[1].fX, SkIntToScalar(3)/5),
SkScalarInterp(pts[0].fY, pts[1].fY, SkIntToScalar(1)/4));
return SkGradientShader::CreateTwoPointRadial(
center1, (pts[1].fX - pts[0].fX) / 7,
center0, (pts[1].fX - pts[0].fX) / 2,
data.fColors, data.fPos, data.fCount, tm);
}
typedef SkShader* (*GradMaker)(const SkPoint pts[2], const GradData& data, SkShader::TileMode tm);
static const GradMaker gGradMakers[] = {
MakeLinear, MakeRadial, MakeSweep, Make2Radial
};
///////////////////////////////////////////////////////////////////////////////
class ShaderTextView : public SampleView {
public:
ShaderTextView() {
this->setBGColor(0xFFDDDDDD);
}
protected:
// overrides from SkEventSink
virtual bool onQuery(SkEvent* evt) {
if (SampleCode::TitleQ(*evt)) {
SampleCode::TitleR(evt, "Shader Text");
return true;
}
return this->INHERITED::onQuery(evt);
}
virtual void onDrawContent(SkCanvas* canvas) {
const char text[] = "Shaded Text";
const int textLen = SK_ARRAY_COUNT(text) - 1;
static int pointSize = 36;
int w = pointSize * textLen;
int h = pointSize;
SkPoint pts[2] = {
{ 0, 0 },
{ SkIntToScalar(w), SkIntToScalar(h) }
};
SkScalar textBase = SkIntToScalar(h/2);
SkShader::TileMode tileModes[] = {
SkShader::kClamp_TileMode,
SkShader::kRepeat_TileMode,
SkShader::kMirror_TileMode
};
static const int gradCount = SK_ARRAY_COUNT(gGradData) *
SK_ARRAY_COUNT(gGradMakers);
static const int bmpCount = SK_ARRAY_COUNT(tileModes) *
SK_ARRAY_COUNT(tileModes);
SkShader* shaders[gradCount + bmpCount];
int shdIdx = 0;
for (size_t d = 0; d < SK_ARRAY_COUNT(gGradData); ++d) {
for (size_t m = 0; m < SK_ARRAY_COUNT(gGradMakers); ++m) {
shaders[shdIdx++] = gGradMakers[m](pts,
gGradData[d],
SkShader::kClamp_TileMode);
}
}
for (size_t tx = 0; tx < SK_ARRAY_COUNT(tileModes); ++tx) {
for (size_t ty = 0; ty < SK_ARRAY_COUNT(tileModes); ++ty) {
shaders[shdIdx++] = MakeBitmapShader(tileModes[tx],
tileModes[ty],
w/8, h);
}
}
SkPaint paint;
paint.setDither(true);
paint.setAntiAlias(true);
paint.setTextSize(SkIntToScalar(pointSize));
canvas->save();
canvas->translate(SkIntToScalar(20), SkIntToScalar(10));
SkPath path;
path.arcTo(SkRect::MakeXYWH(SkIntToScalar(-40), SkIntToScalar(15),
SkIntToScalar(300), SkIntToScalar(90)),
SkIntToScalar(225), SkIntToScalar(90),
false);
path.close();
static const int testsPerCol = 8;
static const int rowHeight = 60;
static const int colWidth = 300;
canvas->save();
for (size_t s = 0; s < SK_ARRAY_COUNT(shaders); s++) {
canvas->save();
size_t i = 2*s;
canvas->translate(SkIntToScalar((i / testsPerCol) * colWidth),
SkIntToScalar((i % testsPerCol) * rowHeight));
paint.setShader(shaders[s])->unref();
canvas->drawText(text, textLen, 0, textBase, paint);
canvas->restore();
canvas->save();
++i;
canvas->translate(SkIntToScalar((i / testsPerCol) * colWidth),
SkIntToScalar((i % testsPerCol) * rowHeight));
canvas->drawTextOnPath(text, textLen, path, NULL, paint);
canvas->restore();
}
canvas->restore();
}
private:
typedef SampleView INHERITED;
};
///////////////////////////////////////////////////////////////////////////////
static SkView* MyFactory() { return new ShaderTextView; }
static SkViewRegister reg(MyFactory);
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