ClipSlide.cpp File Reference

#include "include/core/SkCanvas.h"
#include "include/core/SkColorPriv.h"
#include "include/core/SkFont.h"
#include "include/core/SkPaint.h"
#include "include/core/SkPathBuilder.h"
#include "include/core/SkRRect.h"
#include "include/core/SkShader.h"
#include "src/base/SkRandom.h"
#include "src/core/SkPathPriv.h"
#include "tools/DecodeUtils.h"
#include "tools/Resources.h"
#include "tools/fonts/FontToolUtils.h"
#include "tools/viewer/ClickHandlerSlide.h"
#include "tools/viewer/Slide.h"
#include "src/core/SkEdgeClipper.h"

Go to the source code of this file.

Classes
class	ClipSlide
struct	SkHalfPlane
class	HalfPlaneSlide
class	HalfPlaneSlide2
class	CameraSlide
class	HalfPlaneSlide3
class	HalfPlaneCoonsSlide

Typedefs
typedef void(*	CanvasProc) (SkCanvas *, bool)

Functions
static void	show_text (SkCanvas *canvas, bool doAA)
static void	show_fill (SkCanvas *canvas, bool doAA)
static SkScalar	randRange (SkRandom &rand, SkScalar min, SkScalar max)
static void	show_stroke (SkCanvas *canvas, bool doAA, SkScalar strokeWidth, int n)
static void	show_hair (SkCanvas *canvas, bool doAA)
static void	show_thick (SkCanvas *canvas, bool doAA)
static SkPath	clip (const SkPath &path, SkPoint p0, SkPoint p1)
static void	draw_halfplane (SkCanvas *canvas, SkPoint p0, SkPoint p1, SkColor c)
static SkPath	make_path ()
static void	draw_halfplane (SkCanvas *canvas, const SkHalfPlane &p, SkColor c)
static void	compute_half_planes (const SkMatrix &mx, SkScalar width, SkScalar height, SkHalfPlane planes[4])
static SkM44	inv (const SkM44 &m)
static SkHalfPlane	half_plane_w0 (const SkMatrix &m)

Variables
constexpr int	W = 150
constexpr int	H = 200

Typedef Documentation

CanvasProc

typedef void(* CanvasProc) (SkCanvas *, bool)

Definition at line 103 of file ClipSlide.cpp.

Function Documentation

clip()

static SkPath clip ( const SkPath &  path, SkPoint  p0, SkPoint  p1  )

static

Definition at line 216 of file ClipSlide.cpp.

                                                               {
    SkMatrix mx, inv;
    SkVector v = p1 - p0;
    mx.setAll(v.fX, -v.fY, p0.fX,
              v.fY,  v.fX, p0.fY,
                 0,     0,     1);
    SkAssertResult(mx.invert(&inv));
 
    SkPath rotated;
    path.transform(inv, &rotated);
 
    SkScalar big = 1e28f;
    SkRect clip = {-big, 0, big, big };
 
    struct Rec {
        SkPathBuilder   fResult;
        SkPoint         fPrev = {0, 0};
    } rec;
 
    SkEdgeClipper::ClipPath(rotated, clip, false,
                            [](SkEdgeClipper* clipper, bool newCtr, void* ctx) {
        Rec* rec = (Rec*)ctx;
 
        bool addLineTo = false;
        SkPoint      pts[4];
        SkPath::Verb verb;
        while ((verb = clipper->next(pts)) != SkPath::kDone_Verb) {
            if (newCtr) {
                rec->fResult.moveTo(pts[0]);
                rec->fPrev = pts[0];
                newCtr = false;
            }
 
            if (addLineTo || pts[0] != rec->fPrev) {
                rec->fResult.lineTo(pts[0]);
            }
 
            switch (verb) {
                case SkPath::kLine_Verb:
                    rec->fResult.lineTo(pts[1]);
                    rec->fPrev = pts[1];
                    break;
                case SkPath::kQuad_Verb:
                    rec->fResult.quadTo(pts[1], pts[2]);
                    rec->fPrev = pts[2];
                    break;
                case SkPath::kCubic_Verb:
                    rec->fResult.cubicTo(pts[1], pts[2], pts[3]);
                    rec->fPrev = pts[3];
                    break;
                default: break;
            }
            addLineTo = true;
        }
    }, &rec);
 
    return rec.fResult.detach().makeTransform(mx);
}

compute_half_planes()

static void compute_half_planes ( const SkMatrix &  mx, SkScalar  width, SkScalar  height, SkHalfPlane  planes[4]  )

static

Definition at line 348 of file ClipSlide.cpp.

                                                       {
    SkScalar a = mx[0], b = mx[1], c = mx[2],
             d = mx[3], e = mx[4], f = mx[5],
             g = mx[6], h = mx[7], i = mx[8];
 
    planes[0] = { 2*g - 2*a/width,  2*h - 2*b/width,  2*i - 2*c/width };
    planes[1] = { 2*a/width,        2*b/width,        2*c/width };
    planes[2] = { 2*g - 2*d/height, 2*h - 2*e/height, 2*i - 2*f/height };
    planes[3] = { 2*d/height,       2*e/height,       2*f/height };
}

draw_halfplane() [1/2]

static void draw_halfplane ( SkCanvas *  canvas, const SkHalfPlane &  p, SkColor  c  )

static

Definition at line 342 of file ClipSlide.cpp.

                                                                              {
    SkPoint pts[2];
    p.twoPts(pts);
    draw_halfplane(canvas, pts[0], pts[1], c);
}

draw_halfplane() [2/2]

static void draw_halfplane ( SkCanvas *  canvas, SkPoint  p0, SkPoint  p1, SkColor  c  )

static

Definition at line 275 of file ClipSlide.cpp.

                                                                                {
    SkVector v = p1 - p0;
    p0 = p0 - v * 1000;
    p1 = p1 + v * 1000;
 
    SkPaint paint;
    paint.setColor(c);
    canvas->drawLine(p0, p1, paint);
}

half_plane_w0()

static SkHalfPlane half_plane_w0 ( const SkMatrix &  m )

static

Definition at line 433 of file ClipSlide.cpp.

                                                    {
    return { m[SkMatrix::kMPersp0], m[SkMatrix::kMPersp1], m[SkMatrix::kMPersp2] - 0.05f };
}

inv()

static SkM44 inv ( const SkM44 &  m )

static

Definition at line 427 of file ClipSlide.cpp.

                                 {
    SkM44 inverse;
    SkAssertResult(m.invert(&inverse));
    return inverse;
}

make_path()

static SkPath make_path ( )

static

Definition at line 285 of file ClipSlide.cpp.

                          {
    SkRandom rand;
    auto rand_pt = [&rand]() {
        auto x = rand.nextF();
        auto y = rand.nextF();
        return SkPoint{x * 400, y * 400};
    };
 
    SkPathBuilder path;
    for (int i = 0; i < 4; ++i) {
        SkPoint pts[6];
        for (auto& p : pts) {
            p = rand_pt();
        }
        path.moveTo(pts[0]).quadTo(pts[1], pts[2]).quadTo(pts[3], pts[4]).lineTo(pts[5]);
    }
    return path.detach();
}

randRange()

static SkScalar randRange ( SkRandom &  rand, SkScalar  min, SkScalar  max  )

static

Definition at line 59 of file ClipSlide.cpp.

                                                                      {
    SkASSERT(min <= max);
    return min + rand.nextUScalar1() * (max - min);
}

show_fill()

static void show_fill ( SkCanvas *  canvas, bool  doAA  )

static

Definition at line 39 of file ClipSlide.cpp.

                                                   {
    SkRandom rand;
    SkPaint paint;
    paint.setAntiAlias(doAA);
 
    for (int i = 0; i < 50; ++i) {
        SkRect r;
 
        r.setXYWH(rand.nextSScalar1() * W, rand.nextSScalar1() * H,
                  rand.nextUScalar1() * W, rand.nextUScalar1() * H);
        paint.setColor(rand.nextU());
        canvas->drawRect(r, paint);
 
        r.setXYWH(rand.nextSScalar1() * W, rand.nextSScalar1() * H,
                  rand.nextUScalar1() * W, rand.nextUScalar1() * H);
        paint.setColor(rand.nextU());
        canvas->drawOval(r, paint);
    }
}

show_hair()

static void show_hair ( SkCanvas *  canvas, bool  doAA  )

static

Definition at line 95 of file ClipSlide.cpp.

                                                   {
    show_stroke(canvas, doAA, 0, 150);
}

show_stroke()

static void show_stroke ( SkCanvas *  canvas, bool  doAA, SkScalar  strokeWidth, int  n  )

static

Definition at line 64 of file ClipSlide.cpp.

                                                                                  {
    SkRandom rand;
    SkPaint paint;
    paint.setAntiAlias(doAA);
    paint.setStyle(SkPaint::kStroke_Style);
    paint.setStrokeWidth(strokeWidth);
 
    for (int i = 0; i < n; ++i) {
        SkRect r;
 
        r.setXYWH(rand.nextSScalar1() * W, rand.nextSScalar1() * H,
                  rand.nextUScalar1() * W, rand.nextUScalar1() * H);
        paint.setColor(rand.nextU());
        canvas->drawRect(r, paint);
 
        r.setXYWH(rand.nextSScalar1() * W, rand.nextSScalar1() * H,
                  rand.nextUScalar1() * W, rand.nextUScalar1() * H);
        paint.setColor(rand.nextU());
        canvas->drawOval(r, paint);
 
        const SkScalar minx = -SkIntToScalar(W)/4;
        const SkScalar maxx = 5*SkIntToScalar(W)/4;
        const SkScalar miny = -SkIntToScalar(H)/4;
        const SkScalar maxy = 5*SkIntToScalar(H)/4;
        paint.setColor(rand.nextU());
        canvas->drawLine(randRange(rand, minx, maxx), randRange(rand, miny, maxy),
                         randRange(rand, minx, maxx), randRange(rand, miny, maxy),
                         paint);
    }
}

show_text()

static void show_text ( SkCanvas *  canvas, bool  doAA  )

static

Definition at line 26 of file ClipSlide.cpp.

                                                   {
    SkRandom rand;
    SkPaint paint;
    SkFont font(ToolUtils::DefaultTypeface(), 20);
    font.setEdging(doAA ? SkFont::Edging::kSubpixelAntiAlias : SkFont::Edging::kAlias);
 
    for (int i = 0; i < 200; ++i) {
        paint.setColor((SK_A32_MASK << SK_A32_SHIFT) | rand.nextU());
        canvas->drawString("Hamburgefons", rand.nextSScalar1() * W, rand.nextSScalar1() * H + 20,
                           font, paint);
    }
}

show_thick()

static void show_thick ( SkCanvas *  canvas, bool  doAA  )

static

Definition at line 99 of file ClipSlide.cpp.

                                                    {
    show_stroke(canvas, doAA, SkIntToScalar(5), 50);
}

Variable Documentation

H

constexpr int H = 200

constexpr

Definition at line 24 of file ClipSlide.cpp.

W

constexpr int W = 150

constexpr

Definition at line 23 of file ClipSlide.cpp.