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#include "EdgeDemo.h"
#include "EdgeWalker_Test.h"
#include "ShapeOps.h"
#import "SkCanvas.h"
#import "SkPaint.h"
// Three circles bounce inside a rectangle. The circles describe three, four
// or five points which in turn describe a polygon. The polygon points
// bounce inside the circles. The circles rotate and scale over time. The
// polygons are combined into a single path, simplified, and stroked.
static bool drawCircles(SkCanvas* canvas, int step)
{
const int circles = 3;
int scales[circles];
int angles[circles];
int locs[circles * 2];
int pts[circles * 2 * 4];
int c, p;
for (c = 0; c < circles; ++c) {
scales[c] = abs(10 - (step + c * 4) % 21);
angles[c] = (step + c * 6) % 600;
locs[c * 2] = abs(130 - (step + c * 9) % 261);
locs[c * 2 + 1] = abs(170 - (step + c * 11) % 341);
for (p = 0; p < 4; ++p) {
pts[c * 8 + p * 2] = abs(90 - ((step + c * 121 + p * 13) % 190));
pts[c * 8 + p * 2 + 1] = abs(110 - ((step + c * 223 + p * 17) % 230));
}
}
SkPath path, out;
for (c = 0; c < circles; ++c) {
for (p = 0; p < 4; ++p) {
SkScalar x = pts[c * 8 + p * 2];
SkScalar y = pts[c * 8 + p * 2 + 1];
x *= 3 + scales[c] / 10.0f;
y *= 3 + scales[c] / 10.0f;
SkScalar angle = angles[c] * 3.1415f * 2 / 600;
SkScalar temp = x * cos(angle) - y * sin(angle);
y = x * sin(angle) + y * cos(angle);
x = temp;
x += locs[c * 2] * 200 / 130.0f;
y += locs[c * 2 + 1] * 200 / 170.0f;
x += 50;
// y += 200;
if (p == 0) {
path.moveTo(x, y);
} else {
path.lineTo(x, y);
}
}
path.close();
}
showPath(path, "original:");
simplify(path, true, out);
showPath(out, "simplified:");
SkPaint paint;
paint.setAntiAlias(true);
paint.setStyle(SkPaint::kStroke_Style);
paint.setStrokeWidth(3);
paint.setColor(0x3F007fbF);
canvas->drawPath(path, paint);
paint.setColor(0xFF60FF00);
paint.setStrokeWidth(1);
canvas->drawPath(out, paint);
return true;
}
static void createStar(SkPath& path, SkScalar innerRadius, SkScalar outerRadius,
SkScalar startAngle, int points, SkPoint center) {
SkScalar angle = startAngle;
for (int index = 0; index < points * 2; ++index) {
SkScalar radius = index & 1 ? outerRadius : innerRadius;
SkScalar x = radius * cos(angle);
SkScalar y = radius * sin(angle);
x += center.fX;
y += center.fY;
if (index == 0) {
path.moveTo(x, y);
} else {
path.lineTo(x, y);
}
angle += 3.1415f / points;
}
path.close();
}
static bool drawStars(SkCanvas* canvas, int step)
{
SkPath path, out;
const int stars = 25;
int pts[stars];
static bool initialize = true;
int s;
for (s = 0; s < stars; ++s) {
pts[s] = 4 + (s % 7);
}
SkPoint locs[stars];
SkScalar angles[stars];
SkScalar innerRadius[stars];
SkScalar outerRadius[stars];
const int width = 640;
const int height = 480;
const int margin = 30;
const int minRadius = 120;
const int maxInner = 800;
const int maxOuter = 1153;
for (s = 0; s < stars; ++s) {
int starW = width - margin * 2 + (SkScalar) s * (stars - s) / stars;
locs[s].fX = (int) (step * (1.3f * (s + 1) / stars) + s * 121) % (starW * 2);
if (locs[s].fX > starW) {
locs[s].fX = starW * 2 - locs[s].fX;
}
locs[s].fX += margin;
int starH = height - margin * 2 + (SkScalar) s * s / stars;
locs[s].fY = (int) (step * (1.7f * (s + 1) / stars) + s * 183) % (starH * 2);
if (locs[s].fY > starH) {
locs[s].fY = starH * 2 - locs[s].fY;
}
locs[s].fY += margin;
angles[s] = ((step + s * 47) % (360 * 4)) * 3.1415f / 180 / 4;
innerRadius[s] = (step + s * 30) % (maxInner * 2);
if (innerRadius[s] > maxInner) {
innerRadius[s] = (maxInner * 2) - innerRadius[s];
}
innerRadius[s] = innerRadius[s] / 4 + minRadius;
outerRadius[s] = (step + s * 70) % (maxOuter * 2);
if (outerRadius[s] > maxOuter) {
outerRadius[s] = (maxOuter * 2) - outerRadius[s];
}
outerRadius[s] = outerRadius[s] / 4 + minRadius;
createStar(path, innerRadius[s] / 4.0f, outerRadius[s] / 4.0f,
angles[s], pts[s], locs[s]);
}
#define SHOW_PATH 0
#if SHOW_PATH
showPath(path, "original:");
#endif
#define TEST_SIMPLIFY 01
#if TEST_SIMPLIFY
simplify(path, true, out);
#if SHOW_PATH
showPath(out, "simplified:");
#endif
#endif
SkPaint paint;
paint.setAntiAlias(true);
paint.setStyle(SkPaint::kStroke_Style);
paint.setStrokeWidth(6);
paint.setColor(0x1F003f7f);
canvas->drawPath(path, paint);
paint.setColor(0xFF305F00);
paint.setStrokeWidth(1);
#if TEST_SIMPLIFY
canvas->drawPath(out, paint);
#endif
return true;
}
static bool (*drawDemos[])(SkCanvas* , int) = {
drawStars,
drawCircles
};
static size_t drawDemosCount = sizeof(drawDemos) / sizeof(drawDemos[0]);
static bool (*firstTest)(SkCanvas* , int) = 0;
bool DrawEdgeDemo(SkCanvas* canvas, int step) {
size_t index = 0;
if (firstTest) {
while (index < drawDemosCount && drawDemos[index] != firstTest) {
++index;
}
}
return (*drawDemos[index])(canvas, step);
}
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