/*
* 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 "SkMakeUnique.h"
static sk_sp<SkShader> make_grad(SkScalar w, SkScalar h) {
SkColor colors[] = { 0xFF000000, 0xFF333333 };
SkPoint pts[] = { { 0, 0 }, { w, h } };
return SkGradientShader::MakeLinear(pts, colors, nullptr, 2, SkShader::kClamp_TileMode);
}
class BigGradientView : public SampleView {
public:
BigGradientView() {}
protected:
bool onQuery(SkEvent* evt) override {
if (SampleCode::TitleQ(*evt)) {
SampleCode::TitleR(evt, "BigGradient");
return true;
}
return this->INHERITED::onQuery(evt);
}
void onDrawContent(SkCanvas* canvas) override {
SkRect r;
r.set(0, 0, this->width(), this->height());
SkPaint p;
p.setShader(make_grad(this->width(), this->height()));
canvas->drawRect(r, p);
}
private:
typedef SampleView INHERITED;
};
///////////////////////////////////////////////////////////////////////////////
static SkView* MyFactory() { return new BigGradientView; }
static SkViewRegister reg(MyFactory);
///////////////////////////////////////////////////////////////////////////////
#include "SkRasterHandleAllocator.h"
class GraphicsPort {
protected:
SkCanvas* fCanvas;
public:
GraphicsPort(SkCanvas* canvas) : fCanvas(canvas) {}
virtual ~GraphicsPort() {}
void save() { fCanvas->save(); }
void saveLayer(const SkRect& bounds, SkAlpha alpha) {
fCanvas->saveLayerAlpha(&bounds, alpha);
}
void restore() { fCanvas->restore(); }
void translate(float x, float y) { fCanvas->translate(x, y); }
void scale(float s) { fCanvas->scale(s, s); }
void clip(const SkRect& r) { fCanvas->clipRect(r); }
void drawOval(const SkRect& r, SkColor c) {
SkPaint p;
p.setColor(c);
fCanvas->drawOval(r, p);
}
virtual void drawRect(const SkRect& r, SkColor c) {
SkPaint p;
p.setColor(c);
fCanvas->drawRect(r, p);
}
SkCanvas* peekCanvas() const { return fCanvas; }
};
#ifdef SK_BUILD_FOR_MAC
#include "SkCGUtils.h"
class CGGraphicsPort : public GraphicsPort {
public:
CGGraphicsPort(SkCanvas* canvas) : GraphicsPort(canvas) {}
void drawRect(const SkRect& r, SkColor c) override {
CGContextRef cg = (CGContextRef)fCanvas->accessTopRasterHandle();
CGColorRef color = CGColorCreateGenericRGB(SkColorGetR(c)/255.f,
SkColorGetG(c)/255.f,
SkColorGetB(c)/255.f,
SkColorGetA(c)/255.f);
CGContextSetFillColorWithColor(cg, color);
CGContextFillRect(cg, CGRectMake(r.x(), r.y(), r.width(), r.height()));
}
};
static CGAffineTransform matrix_to_transform(CGContextRef cg, const SkMatrix& ctm) {
SkMatrix matrix;
matrix.setScale(1, -1);
matrix.postTranslate(0, SkIntToScalar(CGBitmapContextGetHeight(cg)));
matrix.preConcat(ctm);
return CGAffineTransformMake(matrix[SkMatrix::kMScaleX],
matrix[SkMatrix::kMSkewY],
matrix[SkMatrix::kMSkewX],
matrix[SkMatrix::kMScaleY],
matrix[SkMatrix::kMTransX],
matrix[SkMatrix::kMTransY]);
}
class Allocator_CG : public SkRasterHandleAllocator {
public:
Allocator_CG() {}
bool allocHandle(const SkImageInfo& info, Rec* rec) override {
// let CG allocate the pixels
CGContextRef cg = SkCreateCGContext(SkPixmap(info, nullptr, 0));
if (!cg) {
return false;
}
rec->fReleaseProc = [](void* pixels, void* ctx){ CGContextRelease((CGContextRef)ctx); };
rec->fReleaseCtx = cg;
rec->fPixels = CGBitmapContextGetData(cg);
rec->fRowBytes = CGBitmapContextGetBytesPerRow(cg);
rec->fHandle = cg;
CGContextSaveGState(cg); // balanced each time updateContext is called
return true;
}
void updateHandle(Handle hndl, const SkMatrix& ctm, const SkIRect& clip) override {
CGContextRef cg = (CGContextRef)hndl;
CGContextRestoreGState(cg);
CGContextSaveGState(cg);
CGContextClipToRect(cg, CGRectMake(clip.x(), clip.y(), clip.width(), clip.height()));
CGContextConcatCTM(cg, matrix_to_transform(cg, ctm));
}
};
#define MyPort CGGraphicsPort
#define MyAllocator Allocator_CG
#elif defined(WIN32)
static RECT toRECT(const SkIRect& r) {
return { r.left(), r.top(), r.right(), r.bottom() };
}
class GDIGraphicsPort : public GraphicsPort {
public:
GDIGraphicsPort(SkCanvas* canvas) : GraphicsPort(canvas) {}
void drawRect(const SkRect& r, SkColor c) override {
HDC hdc = (HDC)fCanvas->accessTopRasterHandle();
COLORREF cr = RGB(SkColorGetR(c), SkColorGetG(c), SkColorGetB(c));// SkEndian_Swap32(c) >> 8;
RECT rounded = toRECT(r.round());
FillRect(hdc, &rounded, CreateSolidBrush(cr));
// Assuming GDI wrote zeros for alpha, this will or-in 0xFF for alpha
SkPaint paint;
paint.setBlendMode(SkBlendMode::kDstATop);
fCanvas->drawRect(r, paint);
}
};
static void DeleteHDCCallback(void*, void* context) {
HDC hdc = static_cast<HDC>(context);
HBITMAP hbitmap = static_cast<HBITMAP>(SelectObject(hdc, nullptr));
DeleteObject(hbitmap);
DeleteDC(hdc);
}
// We use this static factory function instead of the regular constructor so
// that we can create the pixel data before calling the constructor. This is
// required so that we can call the base class' constructor with the pixel
// data.
static bool Create(int width, int height, bool is_opaque, SkRasterHandleAllocator::Rec* rec) {
BITMAPINFOHEADER hdr;
memset(&hdr, 0, sizeof(hdr));
hdr.biSize = sizeof(BITMAPINFOHEADER);
hdr.biWidth = width;
hdr.biHeight = -height; // Minus means top-down bitmap.
hdr.biPlanes = 1;
hdr.biBitCount = 32;
hdr.biCompression = BI_RGB; // No compression.
hdr.biSizeImage = 0;
hdr.biXPelsPerMeter = 1;
hdr.biYPelsPerMeter = 1;
void* pixels;
HBITMAP hbitmap = CreateDIBSection(nullptr, (const BITMAPINFO*)&hdr, 0, &pixels, 0, 0);
if (!hbitmap) {
return false;
}
size_t row_bytes = width * sizeof(SkPMColor);
sk_bzero(pixels, row_bytes * height);
HDC hdc = CreateCompatibleDC(nullptr);
if (!hdc) {
DeleteObject(hbitmap);
return false;
}
SetGraphicsMode(hdc, GM_ADVANCED);
SelectObject(hdc, hbitmap);
rec->fReleaseProc = DeleteHDCCallback;
rec->fReleaseCtx = hdc;
rec->fPixels = pixels;
rec->fRowBytes = row_bytes;
rec->fHandle = hdc;
return true;
}
/**
* Subclass of SkRasterHandleAllocator that returns an HDC as its "handle".
*/
class GDIAllocator : public SkRasterHandleAllocator {
public:
GDIAllocator() {}
bool allocHandle(const SkImageInfo& info, Rec* rec) override {
SkASSERT(info.colorType() == kN32_SkColorType);
return Create(info.width(), info.height(), info.isOpaque(), rec);
}
void updateHandle(Handle handle, const SkMatrix& ctm, const SkIRect& clip_bounds) override {
HDC hdc = static_cast<HDC>(handle);
XFORM xf;
xf.eM11 = ctm[SkMatrix::kMScaleX];
xf.eM21 = ctm[SkMatrix::kMSkewX];
xf.eDx = ctm[SkMatrix::kMTransX];
xf.eM12 = ctm[SkMatrix::kMSkewY];
xf.eM22 = ctm[SkMatrix::kMScaleY];
xf.eDy = ctm[SkMatrix::kMTransY];
SetWorldTransform(hdc, &xf);
RECT clip_bounds_RECT = toRECT(clip_bounds);
HRGN hrgn = CreateRectRgnIndirect(&clip_bounds_RECT);
int result = SelectClipRgn(hdc, hrgn);
SkASSERT(result != ERROR);
result = DeleteObject(hrgn);
SkASSERT(result != 0);
}
};
#define MyPort GDIGraphicsPort
#define MyAllocator GDIAllocator
#endif
#ifdef MyAllocator
class RasterAllocatorSample : public SampleView {
public:
RasterAllocatorSample() {}
protected:
bool onQuery(SkEvent* evt) override {
if (SampleCode::TitleQ(*evt)) {
SampleCode::TitleR(evt, "raster-allocator");
return true;
}
return this->INHERITED::onQuery(evt);
}
void doDraw(GraphicsPort* port) {
SkAutoCanvasRestore acr(port->peekCanvas(), true);
port->drawRect({0, 0, 256, 256}, SK_ColorRED);
port->save();
port->translate(30, 30);
port->drawRect({0, 0, 30, 30}, SK_ColorBLUE);
port->drawOval({10, 10, 20, 20}, SK_ColorWHITE);
port->restore();
port->saveLayer({50, 50, 100, 100}, 0x80);
port->drawRect({55, 55, 95, 95}, SK_ColorGREEN);
port->restore();
port->clip({150, 50, 200, 200});
port->drawRect({0, 0, 256, 256}, 0xFFCCCCCC);
}
void onDrawContent(SkCanvas* canvas) override {
GraphicsPort skp(canvas);
doDraw(&skp);
const SkImageInfo info = SkImageInfo::MakeN32Premul(256, 256);
std::unique_ptr<SkCanvas> c2 =
SkRasterHandleAllocator::MakeCanvas(skstd::make_unique<MyAllocator>(), info);
MyPort cgp(c2.get());
doDraw(&cgp);
SkPixmap pm;
c2->peekPixels(&pm);
SkBitmap bm;
bm.installPixels(pm);
canvas->drawBitmap(bm, 280, 0, nullptr);
}
private:
typedef SampleView INHERITED;
};
DEF_SAMPLE( return new RasterAllocatorSample; )
#endif