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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"
#include "SkGraphics.h"
#include "SkImageDecoder.h"
#include "SkPath.h"
#include "SkRandom.h"
#include "SkRegion.h"
#include "SkShader.h"
#include "SkUtils.h"
#include "SkXfermode.h"
#include "SkColorPriv.h"
#include "SkColorFilter.h"
#include "SkTime.h"
#include "SkTypeface.h"
#include "SkOSFile.h"
#include "SkStream.h"
#include "SkGeometry.h" // private include :(
static SkShader* make_shader0(SkIPoint* size) {
SkBitmap bm;
// SkImageDecoder::DecodeFile("/skimages/progressivejpg.jpg", &bm);
SkImageDecoder::DecodeFile("/skimages/logo.png", &bm);
size->set(bm.width(), bm.height());
return SkShader::CreateBitmapShader(bm, SkShader::kClamp_TileMode,
SkShader::kClamp_TileMode);
}
static SkShader* make_shader1(const SkIPoint& size) {
SkPoint pts[] = { { 0, 0, },
{ SkIntToScalar(size.fX), SkIntToScalar(size.fY) } };
SkColor colors[] = { SK_ColorRED, SK_ColorGREEN, SK_ColorBLUE, SK_ColorRED };
return SkGradientShader::CreateLinear(pts, colors, NULL,
SK_ARRAY_COUNT(colors), SkShader::kMirror_TileMode, NULL);
}
///////////////////////////////////////////////////////////////////////////////
class Patch {
public:
Patch() { sk_bzero(fPts, sizeof(fPts)); }
~Patch() {}
void setPatch(const SkPoint pts[12]) {
memcpy(fPts, pts, 12 * sizeof(SkPoint));
fPts[12] = pts[0]; // the last shall be first
}
void setBounds(int w, int h) { fW = w; fH = h; }
void draw(SkCanvas*, const SkPaint&, int segsU, int segsV,
bool doTextures, bool doColors);
private:
SkPoint fPts[13];
int fW, fH;
};
static void eval_patch_edge(const SkPoint cubic[], SkPoint samples[], int segs) {
SkScalar t = 0;
SkScalar dt = SK_Scalar1 / segs;
samples[0] = cubic[0];
for (int i = 1; i < segs; i++) {
t += dt;
SkEvalCubicAt(cubic, t, &samples[i], NULL, NULL);
}
}
static void eval_sheet(const SkPoint edge[], int nu, int nv, int iu, int iv,
SkPoint* pt) {
const int TL = 0;
const int TR = nu;
const int BR = TR + nv;
const int BL = BR + nu;
SkScalar u = SkIntToScalar(iu) / nu;
SkScalar v = SkIntToScalar(iv) / nv;
SkScalar uv = SkScalarMul(u, v);
SkScalar Uv = SkScalarMul(SK_Scalar1 - u, v);
SkScalar uV = SkScalarMul(u, SK_Scalar1 - v);
SkScalar UV = SkScalarMul(SK_Scalar1 - u, SK_Scalar1 - v);
SkScalar x0 = SkScalarMul(UV, edge[TL].fX) + SkScalarMul(uV, edge[TR].fX) +
SkScalarMul(Uv, edge[BL].fX) + SkScalarMul(uv, edge[BR].fX);
SkScalar y0 = SkScalarMul(UV, edge[TL].fY) + SkScalarMul(uV, edge[TR].fY) +
SkScalarMul(Uv, edge[BL].fY) + SkScalarMul(uv, edge[BR].fY);
SkScalar x = SkScalarMul(SK_Scalar1 - v, edge[TL+iu].fX) +
SkScalarMul(u, edge[TR+iv].fX) +
SkScalarMul(v, edge[BR+nu-iu].fX) +
SkScalarMul(SK_Scalar1 - u, edge[BL+nv-iv].fX) - x0;
SkScalar y = SkScalarMul(SK_Scalar1 - v, edge[TL+iu].fY) +
SkScalarMul(u, edge[TR+iv].fY) +
SkScalarMul(v, edge[BR+nu-iu].fY) +
SkScalarMul(SK_Scalar1 - u, edge[BL+nv-iv].fY) - y0;
pt->set(x, y);
}
static int ScalarTo255(SkScalar v) {
int scale = SkScalarToFixed(v) >> 8;
if (scale < 0) {
scale = 0;
} else if (scale > 255) {
scale = 255;
}
return scale;
}
static SkColor make_color(SkScalar s, SkScalar t) {
int cs = ScalarTo255(s);
int ct = ScalarTo255(t);
return SkColorSetARGB(0xFF, cs, 0, 0) + SkColorSetARGB(0, 0, ct, 0);
}
void Patch::draw(SkCanvas* canvas, const SkPaint& paint, int nu, int nv,
bool doTextures, bool doColors) {
if (nu < 1 || nv < 1) {
return;
}
int i, npts = (nu + nv) * 2;
SkAutoSTMalloc<16, SkPoint> storage(npts + 1);
SkPoint* edge0 = storage.get();
SkPoint* edge1 = edge0 + nu;
SkPoint* edge2 = edge1 + nv;
SkPoint* edge3 = edge2 + nu;
// evaluate the edge points
eval_patch_edge(fPts + 0, edge0, nu);
eval_patch_edge(fPts + 3, edge1, nv);
eval_patch_edge(fPts + 6, edge2, nu);
eval_patch_edge(fPts + 9, edge3, nv);
edge3[nv] = edge0[0]; // the last shall be first
for (i = 0; i < npts; i++) {
// canvas->drawLine(edge0[i].fX, edge0[i].fY, edge0[i+1].fX, edge0[i+1].fY, paint);
}
int row, vertCount = (nu + 1) * (nv + 1);
SkAutoTMalloc<SkPoint> vertStorage(vertCount);
SkPoint* verts = vertStorage.get();
// first row
memcpy(verts, edge0, (nu + 1) * sizeof(SkPoint));
// rows
SkPoint* r = verts;
for (row = 1; row < nv; row++) {
r += nu + 1;
r[0] = edge3[nv - row];
for (int col = 1; col < nu; col++) {
eval_sheet(edge0, nu, nv, col, row, &r[col]);
}
r[nu] = edge1[row];
}
// last row
SkPoint* last = verts + nv * (nu + 1);
for (i = 0; i <= nu; i++) {
last[i] = edge2[nu - i];
}
// canvas->drawPoints(verts, vertCount, paint);
int stripCount = (nu + 1) * 2;
SkAutoTMalloc<SkPoint> stripStorage(stripCount * 2);
SkAutoTMalloc<SkColor> colorStorage(stripCount);
SkPoint* strip = stripStorage.get();
SkPoint* tex = strip + stripCount;
SkColor* colors = colorStorage.get();
SkScalar t = 0;
const SkScalar ds = SK_Scalar1 * fW / nu;
const SkScalar dt = SK_Scalar1 * fH / nv;
r = verts;
for (row = 0; row < nv; row++) {
SkPoint* upper = r;
SkPoint* lower = r + nu + 1;
r = lower;
SkScalar s = 0;
for (i = 0; i <= nu; i++) {
strip[i*2 + 0] = *upper++;
strip[i*2 + 1] = *lower++;
tex[i*2 + 0].set(s, t);
tex[i*2 + 1].set(s, t + dt);
colors[i*2 + 0] = make_color(s/fW, t/fH);
colors[i*2 + 1] = make_color(s/fW, (t + dt)/fH);
s += ds;
}
t += dt;
canvas->drawVertices(SkCanvas::kTriangleStrip_VertexMode, stripCount,
strip, doTextures ? tex : NULL,
doColors ? colors : NULL, NULL,
NULL, 0, paint);
}
}
static void drawpatches(SkCanvas* canvas, const SkPaint& paint, int nu, int nv,
Patch* patch) {
SkAutoCanvasRestore ar(canvas, true);
patch->draw(canvas, paint, 10, 10, false, false);
canvas->translate(SkIntToScalar(180), 0);
patch->draw(canvas, paint, 10, 10, true, false);
canvas->translate(SkIntToScalar(180), 0);
patch->draw(canvas, paint, 10, 10, false, true);
canvas->translate(SkIntToScalar(180), 0);
patch->draw(canvas, paint, 10, 10, true, true);
}
class PatchView : public SampleView {
SkShader* fShader0;
SkShader* fShader1;
SkIPoint fSize0, fSize1;
SkPoint fPts[12];
public:
PatchView() {
fShader0 = make_shader0(&fSize0);
fSize1 = fSize0;
if (fSize0.fX == 0 || fSize0.fY == 0) {
fSize1.set(2, 2);
}
fShader1 = make_shader1(fSize1);
const SkScalar S = SkIntToScalar(50);
const SkScalar T = SkIntToScalar(40);
fPts[0].set(S*0, T);
fPts[1].set(S*1, T);
fPts[2].set(S*2, T);
fPts[3].set(S*3, T);
fPts[4].set(S*3, T*2);
fPts[5].set(S*3, T*3);
fPts[6].set(S*3, T*4);
fPts[7].set(S*2, T*4);
fPts[8].set(S*1, T*4);
fPts[9].set(S*0, T*4);
fPts[10].set(S*0, T*3);
fPts[11].set(S*0, T*2);
this->setBGColor(SK_ColorGRAY);
}
virtual ~PatchView() {
SkSafeUnref(fShader0);
SkSafeUnref(fShader1);
}
protected:
// overrides from SkEventSink
virtual bool onQuery(SkEvent* evt) {
if (SampleCode::TitleQ(*evt)) {
SampleCode::TitleR(evt, "Patch");
return true;
}
return this->INHERITED::onQuery(evt);
}
virtual void onDrawContent(SkCanvas* canvas) {
SkPaint paint;
paint.setDither(true);
paint.setFilterBitmap(true);
canvas->translate(SkIntToScalar(20), 0);
Patch patch;
paint.setShader(fShader0);
if (fSize0.fX == 0) {
fSize0.fX = 1;
}
if (fSize0.fY == 0) {
fSize0.fY = 1;
}
patch.setBounds(fSize0.fX, fSize0.fY);
patch.setPatch(fPts);
drawpatches(canvas, paint, 10, 10, &patch);
paint.setShader(NULL);
paint.setAntiAlias(true);
paint.setStrokeWidth(SkIntToScalar(5));
canvas->drawPoints(SkCanvas::kPoints_PointMode, SK_ARRAY_COUNT(fPts), fPts, paint);
canvas->translate(0, SkIntToScalar(300));
paint.setAntiAlias(false);
paint.setShader(fShader1);
patch.setBounds(fSize1.fX, fSize1.fY);
drawpatches(canvas, paint, 10, 10, &patch);
}
class PtClick : public Click {
public:
int fIndex;
PtClick(SkView* view, int index) : Click(view), fIndex(index) {}
};
static bool hittest(const SkPoint& pt, SkScalar x, SkScalar y) {
return SkPoint::Length(pt.fX - x, pt.fY - y) < SkIntToScalar(5);
}
virtual SkView::Click* onFindClickHandler(SkScalar x, SkScalar y,
unsigned modi) SK_OVERRIDE {
for (size_t i = 0; i < SK_ARRAY_COUNT(fPts); i++) {
if (hittest(fPts[i], x, y)) {
return new PtClick(this, i);
}
}
return this->INHERITED::onFindClickHandler(x, y, modi);
}
virtual bool onClick(Click* click) {
fPts[((PtClick*)click)->fIndex].set(click->fCurr.fX, click->fCurr.fY);
this->inval(NULL);
return true;
}
private:
typedef SampleView INHERITED;
};
//////////////////////////////////////////////////////////////////////////////
static SkView* MyFactory() { return new PatchView; }
static SkViewRegister reg(MyFactory);
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