drawimageset.cpp File Reference

#include "gm/gm.h"
#include "include/core/SkBlendMode.h"
#include "include/core/SkCanvas.h"
#include "include/core/SkColor.h"
#include "include/core/SkColorFilter.h"
#include "include/core/SkColorSpace.h"
#include "include/core/SkImage.h"
#include "include/core/SkImageInfo.h"
#include "include/core/SkMatrix.h"
#include "include/core/SkPaint.h"
#include "include/core/SkPoint.h"
#include "include/core/SkRect.h"
#include "include/core/SkRefCnt.h"
#include "include/core/SkScalar.h"
#include "include/core/SkShader.h"
#include "include/core/SkSize.h"
#include "include/core/SkString.h"
#include "include/core/SkSurface.h"
#include "include/core/SkTileMode.h"
#include "include/core/SkTypes.h"
#include "include/effects/SkGradientShader.h"
#include "include/gpu/GrDirectContext.h"
#include "tools/GpuToolUtils.h"
#include "tools/ToolUtils.h"
#include <algorithm>
#include <initializer_list>
#include <utility>

Go to the source code of this file.

Classes
class	skiagm::DrawImageSetGM
class	skiagm::DrawImageSetRectToRectGM
class	skiagm::DrawImageSetAlphaOnlyGM

Namespaces
namespace	skiagm

Functions
static void	make_image_tiles (int tileW, int tileH, int m, int n, const SkColor colors[4], SkCanvas::ImageSetEntry set[], const SkColor bgColor=SK_ColorLTGRAY)

Function Documentation

make_image_tiles()

static void make_image_tiles ( int  tileW, int  tileH, int  m, int  n, const SkColor  colors[4], SkCanvas::ImageSetEntry  set[], const SkColor  bgColor = SK_ColorLTGRAY  )

static

Definition at line 38 of file drawimageset.cpp.

                                                                                                {
    const int w = tileW * m;
    const int h = tileH * n;
    auto surf = SkSurfaces::Raster(
            SkImageInfo::Make(w, h, kRGBA_8888_SkColorType, kPremul_SkAlphaType));
    surf->getCanvas()->clear(bgColor);
 
    static constexpr SkScalar kStripeW = 10;
    static constexpr SkScalar kStripeSpacing = 30;
    SkPaint paint;
 
    SkPoint pts1[] = {{0.f, 0.f}, {(SkScalar)w, (SkScalar)h}};
    auto grad = SkGradientShader::MakeLinear(pts1, colors, nullptr, 2, SkTileMode::kClamp);
    paint.setShader(std::move(grad));
    paint.setAntiAlias(true);
    paint.setStyle(SkPaint::kStroke_Style);
    paint.setStrokeWidth(kStripeW);
    SkPoint stripePts[] = {{-w - kStripeW, -kStripeW}, {kStripeW, h + kStripeW}};
    while (stripePts[0].fX <= w) {
        surf->getCanvas()->drawPoints(SkCanvas::kLines_PointMode, 2, stripePts, paint);
        stripePts[0].fX += kStripeSpacing;
        stripePts[1].fX += kStripeSpacing;
    }
 
    SkPoint pts2[] = {{0.f, (SkScalar)h}, {(SkScalar)w, 0.f}};
    grad = SkGradientShader::MakeLinear(pts2, colors + 2, nullptr, 2, SkTileMode::kClamp);
    paint.setShader(std::move(grad));
    paint.setBlendMode(SkBlendMode::kMultiply);
    stripePts[0] = {-w - kStripeW, h + kStripeW};
    stripePts[1] = {kStripeW, -kStripeW};
    while (stripePts[0].fX <= w) {
        surf->getCanvas()->drawPoints(SkCanvas::kLines_PointMode, 2, stripePts, paint);
        stripePts[0].fX += kStripeSpacing;
        stripePts[1].fX += kStripeSpacing;
    }
    auto fullImage = surf->makeImageSnapshot();
    for (int y = 0; y < n; ++y) {
        for (int x = 0; x < m; ++x) {
            // Images will have 1 pixel of overlap at interior seams for filtering continuity.
            SkIRect subset = SkIRect::MakeXYWH(x * tileW - 1, y * tileH - 1, tileW + 2, tileH + 2);
            set[y * m + x].fAAFlags = SkCanvas::kNone_QuadAAFlags;
            if (x == 0) {
                subset.fLeft = 0;
                set[y * m + x].fAAFlags |= SkCanvas::kLeft_QuadAAFlag;
            }
            if (x == m - 1) {
                subset.fRight = w;
                set[y * m + x].fAAFlags |= SkCanvas::kRight_QuadAAFlag;
            }
            if (y == 0) {
                subset.fTop = 0;
                set[y * m + x].fAAFlags |= SkCanvas::kTop_QuadAAFlag;
            }
            if (y == n - 1) {
                subset.fBottom = h;
                set[y * m + x].fAAFlags |= SkCanvas::kBottom_QuadAAFlag;
            }
            set[y * m + x].fImage = fullImage->makeSubset(nullptr, subset);
            set[y * m + x].fSrcRect =
                    SkRect::MakeXYWH(x == 0 ? 0 : 1, y == 0 ? 0 : 1, tileW, tileH);
            set[y * m + x].fDstRect = SkRect::MakeXYWH(x * tileW, y * tileH, tileW, tileH);
            set[y * m + x].fAlpha = 1.f;
            SkASSERT(set[y * m + x].fImage);
        }
    }
}