skia2/samplecode/SamplePolyToPoly.cpp
Cary Clark 2a475eae62 add drawString helper to canvas
Many tests and examples use drawText with
a guess of how long the text is in bytes,
or a call to strlen(). Add a helper to
SkCanvas to simplify these examples.

Add another helper for SkString.

R=reed@google.com

Change-Id: I0204a31e938f065606f08ee7cd9a6b36db791ee2
Reviewed-on: https://skia-review.googlesource.com/13642
Commit-Queue: Cary Clark <caryclark@google.com>
Reviewed-by: Cary Clark <caryclark@google.com>
Reviewed-by: Mike Reed <reed@google.com>
Reviewed-by: Cary Clark <caryclark@skia.org>
2017-04-28 20:41:04 +00:00

168 lines
5.3 KiB
C++

/*
* 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 "SkGraphics.h"
#include "SkPath.h"
#include "SkRandom.h"
#include "SkTime.h"
extern bool SkSetPoly3To3(SkMatrix* matrix, const SkPoint src[3], const SkPoint dst[3]);
class PolyToPolyView : public SampleView {
public:
PolyToPolyView() {
// tests
{
SkPoint src[] = { { 0, 0 },
{ SK_Scalar1, 0 },
{ 0, SK_Scalar1 } };
SkPoint dst[] = { { 0, 0 },
{ 2*SK_Scalar1, 0 },
{ 0, 2*SK_Scalar1 } };
SkMatrix m1, m2;
(void) m1.setPolyToPoly(src, dst, 3);
m2.reset();
m2.set(SkMatrix::kMScaleX, dst[1].fX - dst[0].fX);
m2.set(SkMatrix::kMSkewX, dst[2].fX - dst[0].fX);
m2.set(SkMatrix::kMTransX, dst[0].fX);
m2.set(SkMatrix::kMSkewY, dst[1].fY - dst[0].fY);
m2.set(SkMatrix::kMScaleY, dst[2].fY - dst[0].fY);
m2.set(SkMatrix::kMTransY, dst[0].fY);
m1.reset();
const SkScalar src1[] = {
0, 0, 0, 427, 316, 427, 316, 0
};
const SkScalar dst1[] = {
158, 177.5f, 158, 249.5f,
158, 604.5f, 158, -177.5f
};
(void) m2.setPolyToPoly((const SkPoint*)src1, (SkPoint*)dst1, 4);
{
const SkPoint src[] = {
{ SkIntToScalar(1), SkIntToScalar(0) },
{ SkIntToScalar(4), SkIntToScalar(7) },
{ SkIntToScalar(10), SkIntToScalar(2) }
};
const SkPoint dst[] = {
{ SkIntToScalar(4), SkIntToScalar(2) },
{ SkIntToScalar(45), SkIntToScalar(26) },
{ SkIntToScalar(32), SkIntToScalar(17) }
};
SkMatrix m0;
m0.setPolyToPoly(src, dst, 3);
// SkMatrix m1;
// SkSetPoly3To3(&m1, src, dst);
// m0.dump();
// m1.dump();
}
}
}
protected:
// overrides from SkEventSink
virtual bool onQuery(SkEvent* evt) {
if (SampleCode::TitleQ(*evt)) {
SampleCode::TitleR(evt, "PolyToPolyView");
return true;
}
return this->INHERITED::onQuery(evt);
}
static void doDraw(SkCanvas* canvas, SkPaint* paint, const int isrc[],
const int idst[], int count) {
SkMatrix matrix;
SkPoint src[4], dst[4];
for (int i = 0; i < count; i++) {
src[i].set(SkIntToScalar(isrc[2*i+0]), SkIntToScalar(isrc[2*i+1]));
dst[i].set(SkIntToScalar(idst[2*i+0]), SkIntToScalar(idst[2*i+1]));
}
canvas->save();
matrix.setPolyToPoly(src, dst, count);
canvas->concat(matrix);
paint->setColor(SK_ColorGRAY);
paint->setStyle(SkPaint::kStroke_Style);
const SkScalar D = SkIntToScalar(64);
canvas->drawRect(SkRect::MakeWH(D, D), *paint);
canvas->drawLine(0, 0, D, D, *paint);
canvas->drawLine(0, D, D, 0, *paint);
SkPaint::FontMetrics fm;
paint->getFontMetrics(&fm);
paint->setColor(SK_ColorRED);
paint->setStyle(SkPaint::kFill_Style);
SkScalar x = D/2;
float y = D/2 - (fm.fAscent + fm.fDescent)/2;
SkString str;
str.appendS32(count);
canvas->drawString(str,
x, y,
*paint);
canvas->restore();
}
virtual void onDrawContent(SkCanvas* canvas) {
SkPaint paint;
paint.setAntiAlias(true);
paint.setStrokeWidth(SkIntToScalar(4));
paint.setTextSize(SkIntToScalar(40));
paint.setTextAlign(SkPaint::kCenter_Align);
canvas->save();
canvas->translate(SkIntToScalar(10), SkIntToScalar(10));
// translate (1 point)
const int src1[] = { 0, 0 };
const int dst1[] = { 5, 5 };
doDraw(canvas, &paint, src1, dst1, 1);
canvas->restore();
canvas->save();
canvas->translate(SkIntToScalar(160), SkIntToScalar(10));
// rotate/uniform-scale (2 points)
const int src2[] = { 32, 32, 64, 32 };
const int dst2[] = { 32, 32, 64, 48 };
doDraw(canvas, &paint, src2, dst2, 2);
canvas->restore();
canvas->save();
canvas->translate(SkIntToScalar(10), SkIntToScalar(110));
// rotate/skew (3 points)
const int src3[] = { 0, 0, 64, 0, 0, 64 };
const int dst3[] = { 0, 0, 96, 0, 24, 64 };
doDraw(canvas, &paint, src3, dst3, 3);
canvas->restore();
canvas->save();
canvas->translate(SkIntToScalar(160), SkIntToScalar(110));
// perspective (4 points)
const int src4[] = { 0, 0, 64, 0, 64, 64, 0, 64 };
const int dst4[] = { 0, 0, 96, 0, 64, 96, 0, 64 };
doDraw(canvas, &paint, src4, dst4, 4);
canvas->restore();
}
private:
typedef SampleView INHERITED;
};
//////////////////////////////////////////////////////////////////////////////
static SkView* MyFactory() { return new PolyToPolyView; }
static SkViewRegister reg(MyFactory);