imageblurrepeatmode.cpp File Reference

#include "gm/gm.h"
#include "include/core/SkBitmap.h"
#include "include/core/SkCanvas.h"
#include "include/core/SkColor.h"
#include "include/core/SkImage.h"
#include "include/core/SkImageFilter.h"
#include "include/core/SkImageInfo.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/SkSurface.h"
#include "include/effects/SkImageFilters.h"
#include "tools/ToolUtils.h"
#include <initializer_list>
#include <utility>

Go to the source code of this file.

Classes
class	skiagm::ImageBlurRepeatModeGM

Namespaces
namespace	skiagm

Functions
static sk_sp< SkImage >	make_image (SkCanvas *canvas, int direction)
static void	draw_image (SkCanvas *canvas, const sk_sp< SkImage > image, sk_sp< SkImageFilter > filter)
	DEF_SIMPLE_GM (imageblurrepeatunclipped, canvas, 256, 128)

Function Documentation

DEF_SIMPLE_GM()

DEF_SIMPLE_GM	(	imageblurrepeatunclipped	,
		canvas	,
		256	,
		128
	)

Definition at line 138 of file imageblurrepeatmode.cpp.

                                                          {
    // To show translucency
    auto checkerboard = ToolUtils::create_checkerboard_image(256, 128, SK_ColorLTGRAY,
                                                             SK_ColorGRAY, 8);
    canvas->drawImage(checkerboard, 0, 0);
 
    // Make an image with one red and one blue band
    SkBitmap bmp;
    bmp.allocN32Pixels(100, 20);
    bmp.eraseArea(SkIRect::MakeWH(100, 10), SK_ColorRED);
    bmp.eraseArea(SkIRect::MakeXYWH(0, 10, 100, 10), SK_ColorBLUE);
 
    auto img = bmp.asImage();
    // The blur filter uses a repeat crop applied to the image bounds to define the tiling geometry,
    // but the crop IF is created directly since the tilemode factory for ::Blur also adds a kDecal
    // post-crop that is undesired for this GM.
    auto filter = SkImageFilters::Blur(0, 10,
            SkImageFilters::Crop(SkRect::Make(img->bounds()), SkTileMode::kRepeat, nullptr));
    SkPaint paint;
    paint.setImageFilter(std::move(filter));
 
    // Draw the blurred image once with a clip that shows the repeat is tiled several times.
    // 3xsigma is used to match the historic, but underspecified behavior for when kRepeat was used
    // with no crop rect (which must now be provided or kRepeat is ignored).
    canvas->translate(0, 50);
    canvas->save();
        canvas->clipIRect(img->bounds().makeOutset(0, 30));
        canvas->drawImage(img, 0, 0, SkSamplingOptions(), &paint);
    canvas->restore();
 
    // Draw the blurred image with a clip positioned such that the draw would be excluded except
    // that the image filter causes it to intersect with the clip. It should look like the
    // left image, but clipped to the debug-black rectangle.
    canvas->translate(110, 0);
    canvas->save();
        canvas->clipIRect(SkIRect::MakeXYWH(0, -30, 100, 10));
        canvas->drawImage(img, 0, 0, SkSamplingOptions(), &paint);
    canvas->restore();
 
    // Visualize the clip
    SkPaint line;
    line.setStyle(SkPaint::kStroke_Style);
    canvas->drawRect(SkRect::MakeXYWH(0, -30, 99, 9), line);
}

draw_image()

static void draw_image ( SkCanvas *  canvas, const sk_sp< SkImage >  image, sk_sp< SkImageFilter >  filter  )

static

Definition at line 64 of file imageblurrepeatmode.cpp.

                                                                                                  {
    SkAutoCanvasRestore acr(canvas, true);
    SkPaint paint;
    paint.setImageFilter(std::move(filter));
 
    canvas->translate(SkIntToScalar(30), 0);
    canvas->clipIRect(image->bounds());
    canvas->drawImage(image, 0, 0, SkSamplingOptions(), &paint);
}

make_image()

static sk_sp< SkImage > make_image ( SkCanvas *  canvas, int  direction  )

static

Definition at line 28 of file imageblurrepeatmode.cpp.

                                                                  {
    SkImageInfo info = SkImageInfo::MakeN32Premul(250, 200);
    auto        surface = ToolUtils::makeSurface(canvas, info);
    SkCanvas* c = surface->getCanvas();
    SkPaint paint;
    paint.setAntiAlias(true);
 
    const SkColor colors[] = {
        SK_ColorRED, SK_ColorBLUE, SK_ColorGREEN, SK_ColorYELLOW, SK_ColorBLACK
    };
 
    int width = 25;
    bool xDirection = (direction & 0x1) == 1;
    bool yDirection = (direction & 0x2) == 2;
    if (xDirection) {
        for (int x = 0; x < info.width(); x += width) {
            paint.setColor(colors[x/width % 5]);
            if (yDirection) {
                paint.setAlphaf(0.5f);
            }
            c->drawRect(SkRect::MakeXYWH(x, 0, width, info.height()), paint);
        }
    }
 
    if (yDirection) {
        for (int y = 0; y < info.height(); y += width) {
            paint.setColor(colors[y/width % 5]);
            if (xDirection) {
                paint.setAlphaf(0.5f);
            }
            c->drawRect(SkRect::MakeXYWH(0, y, info.width(), width), paint);
        }
    }
    return surface->makeImageSnapshot();
}