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2026-04-10 15:06:11 +08:00

621 lines
16 KiB
TypeScript

/**
* 图形涂色方法
* 根据图形类型绘制到Canvas
*
* 支持的图形类型:
* - circle:圆形
* - ellipse:椭圆
* - square:正方形
* - rectangle:矩形
* - triangle:三角形
* - parallelogram:平行四边形
* - diamond:菱形
* - trapezoid:梯形
* - pentagon:五边形
* - hexagon:六边形
* - pentagram:五角星
* - heart:心形
* - semicircle:半圆
* - sector:扇形
* - ring:圆环
*/
import { ShapeCard } from '../constants/shapes';
// 绘制各种图形的辅助函数
// 绘制圆形
function drawCircle(
ctx: RenderingContext,
x: number,
y: number,
radius: number,
fillColor: string,
) {
ctx.beginPath();
ctx.arc(x, y, radius, 0, Math.PI * 2);
if (fillColor !== 'transparent') {
ctx.fillStyle = fillColor;
ctx.fill();
}
ctx.strokeStyle = '#141414';
ctx.lineWidth = 2;
ctx.stroke();
}
// 绘制椭圆形
function drawEllipse(
ctx: RenderingContext,
x: number,
y: number,
rx: number,
ry: number,
fillColor: string,
) {
ctx.beginPath();
ctx.ellipse(x, y, rx, ry, 0, 0, Math.PI * 2);
if (fillColor !== 'transparent') {
ctx.fillStyle = fillColor;
ctx.fill();
}
ctx.strokeStyle = '#141414';
ctx.lineWidth = 2;
ctx.stroke();
}
// 绘制正方形
function drawSquare(
ctx: RenderingContext,
x: number,
y: number,
size: number,
fillColor: string,
) {
if (fillColor !== 'transparent') {
ctx.fillStyle = fillColor;
ctx.fillRect(x - size / 2, y - size / 2, size, size);
}
ctx.strokeStyle = '#141414';
ctx.lineWidth = 2;
ctx.strokeRect(x - size / 2, y - size / 2, size, size);
}
// 绘制矩形
function drawRectangle(
ctx: RenderingContext,
x: number,
y: number,
width: number,
height: number,
fillColor: string,
) {
if (fillColor !== 'transparent') {
ctx.fillStyle = fillColor;
ctx.fillRect(x - width / 2, y - height / 2, width, height);
}
ctx.strokeStyle = '#141414';
ctx.lineWidth = 2;
ctx.strokeRect(x - width / 2, y - height / 2, width, height);
}
// 绘制三角形(可指定类型:钝角、直角、锐角)
function drawTriangle(
ctx: RenderingContext,
x: number,
y: number,
size: number,
type: string,
fillColor: string,
) {
ctx.beginPath();
switch (type) {
case 'obtuse':
ctx.moveTo(x - size * 0.6, y - size * 0.4);
ctx.lineTo(x + size * 0.8, y + size * 0.6);
ctx.lineTo(x - size * 0.2, y + size * 0.4);
break;
case 'right':
ctx.moveTo(x - size * 0.4, y - size * 0.4);
ctx.lineTo(x - size * 0.4, y + size * 0.6);
ctx.lineTo(x + size * 0.6, y + size * 0.6);
break;
case 'acute':
default:
ctx.moveTo(x, y - size * 0.5);
ctx.lineTo(x - size * 0.5, y + size * 0.5);
ctx.lineTo(x + size * 0.5, y + size * 0.5);
break;
}
ctx.closePath();
if (fillColor !== 'transparent') {
ctx.fillStyle = fillColor;
ctx.fill();
}
ctx.strokeStyle = '#141414';
ctx.lineWidth = 2;
ctx.stroke();
}
// 绘制平行四边形
function drawParallelogram(
ctx: RenderingContext,
x: number,
y: number,
width: number,
height: number,
fillColor: string,
) {
const offset = width * 0.2;
ctx.beginPath();
ctx.moveTo(x - width / 2 + offset, y - height / 2);
ctx.lineTo(x + width / 2 + offset, y - height / 2);
ctx.lineTo(x + width / 2 - offset, y + height / 2);
ctx.lineTo(x - width / 2 - offset, y + height / 2);
ctx.closePath();
if (fillColor !== 'transparent') {
ctx.fillStyle = fillColor;
ctx.fill();
}
ctx.strokeStyle = '#141414';
ctx.lineWidth = 2;
ctx.stroke();
}
// 绘制菱形
function drawDiamond(
ctx: RenderingContext,
x: number,
y: number,
size: number,
fillColor: string,
) {
// 参考SVG: <polygon points="50,15 70,50 50,85 30,50"/>
// 以(x, y)为中心,size为半高,按SVG比例映射四个点
// SVG中心(50,50),顶点(50,15),右(70,50),下(50,85),左(30,50)
// 计算比例
// 顶点: (0, -0.7*size)
// 右: (0.4*size, 0)
// 下: (0, 0.7*size)
// 左: (-0.4*size, 0)
const topY = y - size * 0.7;
const rightX = x + size * 0.4;
const bottomY = y + size * 0.7;
const leftX = x - size * 0.4;
ctx.beginPath();
ctx.moveTo(x, topY); // 顶点
ctx.lineTo(rightX, y); // 右
ctx.lineTo(x, bottomY); // 下
ctx.lineTo(leftX, y); // 左
ctx.closePath();
if (fillColor !== 'transparent') {
ctx.fillStyle = fillColor;
ctx.fill();
}
ctx.strokeStyle = '#141414';
ctx.lineWidth = 2;
ctx.stroke();
}
// 绘制梯形
// 保证绘制的是等腰梯形:上下底居中,左右腰等长
function drawTrapezoid(
ctx: RenderingContext,
x: number,
y: number,
width: number,
height: number,
fillColor: string,
) {
// topWidth 为上底宽度,width 为下底宽度
const topWidth = width * 0.6; // 上底
const bottomWidth = width; // 下底
const halfHeight = height / 2;
// 上底中心点与下底中心点重合,左右对称
ctx.beginPath();
// 上底左点
ctx.moveTo(x - topWidth / 2, y - halfHeight);
// 上底右点
ctx.lineTo(x + topWidth / 2, y - halfHeight);
// 下底右点
ctx.lineTo(x + bottomWidth / 2, y + halfHeight);
// 下底左点
ctx.lineTo(x - bottomWidth / 2, y + halfHeight);
ctx.closePath();
if (fillColor !== 'transparent') {
ctx.fillStyle = fillColor;
ctx.fill();
}
ctx.strokeStyle = '#141414';
ctx.lineWidth = 2;
ctx.stroke();
}
// 绘制多边形
function drawPolygon(
ctx: RenderingContext,
x: number,
y: number,
radius: number,
sides: number,
fillColor: string,
) {
ctx.beginPath();
for (let i = 0; i < sides; i++) {
const angle = (i * 2 * Math.PI) / sides - Math.PI / 2;
const px = x + Math.cos(angle) * radius;
const py = y + Math.sin(angle) * radius;
if (i === 0) ctx.moveTo(px, py);
else ctx.lineTo(px, py);
}
ctx.closePath();
if (fillColor !== 'transparent') {
ctx.fillStyle = fillColor;
ctx.fill();
}
ctx.strokeStyle = '#141414';
ctx.lineWidth = 2;
ctx.stroke();
}
// 绘制星形(五角星等)
// 按SVG <polygon points="50,20 61,42 85,44 67,60 71,85 50,75 29,85 33,60 15,44 39,42"> 路径绘制五角星
function drawStar(
ctx: RenderingContext,
x: number,
y: number,
radius: number,
points: number,
fillColor: string,
) {
// SVG原始点
const svgPoints = [
[50, 20],
[61, 42],
[85, 44],
[67, 60],
[71, 85],
[50, 75],
[29, 85],
[33, 60],
[15, 44],
[39, 42],
];
// SVG中心(50,50),最大半径约为35(从50,50到15,44的距离),SVG坐标范围大致为[15,85]
// 归一化到以(x, y)为中心,radius为最大半径
const svgCenterX = 50;
const svgCenterY = 50;
const svgRadius = 35; // 50-15=35
ctx.beginPath();
svgPoints.forEach(([px, py], idx) => {
const nx = x + ((px - svgCenterX) / svgRadius) * radius;
const ny = y + ((py - svgCenterY) / svgRadius) * radius;
if (idx === 0) ctx.moveTo(nx, ny);
else ctx.lineTo(nx, ny);
});
ctx.closePath();
if (fillColor !== 'transparent') {
ctx.fillStyle = fillColor;
ctx.fill();
}
ctx.strokeStyle = '#141414';
ctx.lineWidth = 2;
ctx.stroke();
}
// 绘制爱心
function drawHeart(
ctx: RenderingContext,
x: number,
y: number,
size: number,
fillColor: string,
) {
// 放大爱心:将原本的缩放比例从60缩小为50,使爱心整体变大
// 以SVG路径为参考,原始SVG中心为(50,50),宽高约为60x60
// 这里size为整体缩放,x,y为中心点
// SVG关键点:M50,35 C35,20 20,35 25,50 C30,65 50,80 50,80 C50,80 70,65 75,50 C80,35 65,20 50,35Z
// 归一化函数
const scale = 40; // 原来是60,改为50,放大
function tx(px: number) {
return x + ((px - 50) / scale) * size;
}
function ty(py: number) {
return y + ((py - 50) / scale) * size;
}
ctx.beginPath();
ctx.moveTo(tx(50), ty(35));
ctx.bezierCurveTo(tx(35), ty(20), tx(20), ty(35), tx(25), ty(50));
ctx.bezierCurveTo(tx(30), ty(65), tx(50), ty(80), tx(50), ty(80));
ctx.bezierCurveTo(tx(50), ty(80), tx(70), ty(65), tx(75), ty(50));
ctx.bezierCurveTo(tx(80), ty(35), tx(65), ty(20), tx(50), ty(35));
ctx.closePath();
if (fillColor !== 'transparent') {
ctx.fillStyle = fillColor;
ctx.fill();
}
ctx.strokeStyle = '#141414';
ctx.lineWidth = 2;
ctx.stroke();
}
// 绘制半圆
function drawSemicircle(
ctx: RenderingContext,
x: number,
y: number,
radius: number,
fillColor: string,
) {
const verticalOffset = radius * 0.5;
y = y + verticalOffset;
ctx.beginPath();
// ctx.moveTo(x, y + verticalOffset);
// 圆弧从左(180°,Math.PI)到右(0°),逆时针画半圆,圆弧在正上方
ctx.arc(x, y, radius, Math.PI, 0, false);
ctx.closePath();
if (fillColor !== 'transparent') {
ctx.fillStyle = fillColor;
ctx.fill();
}
ctx.strokeStyle = '#141414';
ctx.lineWidth = 2;
ctx.stroke();
}
// 绘制扇形,圆弧在正上方
function drawSector(
ctx: RenderingContext,
x: number,
y: number,
radius: number,
fillColor: string,
) {
// 为了让扇形垂直方向居中,需要将整个扇形向下平移一定距离
// 扇形的质心大约在半径的 0.6 倍处(120°扇形),这里经验值调整
const verticalOffset = radius * 0.5;
ctx.beginPath();
ctx.moveTo(x, y + verticalOffset);
// 扇形圆弧从左上(-135°)到右上(-45°),即从 -3/4π 到 -1/4π,圆弧在正上方
ctx.arc(
x,
y + verticalOffset,
radius,
(-3 * Math.PI) / 4,
-Math.PI / 4,
false,
);
ctx.closePath();
if (fillColor !== 'transparent') {
ctx.fillStyle = fillColor;
ctx.fill();
}
ctx.strokeStyle = '#141414';
ctx.lineWidth = 2;
ctx.stroke();
}
// 绘制圆环(修正避免中间出现一条线)
function drawRing(
ctx: RenderingContext,
x: number,
y: number,
radius: number,
fillColor: string,
) {
const innerRadius = radius * 0.5;
ctx.save();
ctx.beginPath();
// 外圆,顺时针
ctx.arc(x, y, radius, 0, Math.PI * 2, false);
// 关键:移动到内圆起点,避免连接线
ctx.moveTo(x + innerRadius, y);
// 内圆,逆时针
ctx.arc(x, y, innerRadius, 0, Math.PI * 2, true);
ctx.closePath();
if (fillColor !== 'transparent') {
ctx.fillStyle = fillColor;
ctx.fill('evenodd');
}
ctx.strokeStyle = '#141414';
ctx.lineWidth = 2;
ctx.stroke();
ctx.restore();
}
/**
* 根据图形类型绘制到Canvas
* @param ctx Canvas上下文
* @param shape 图形对象
* @param x 起始x坐标
* @param y 起始y坐标
* @param size 图形大小
* @param fillColor 填充颜色
*/
export function drawShape(
ctx: RenderingContext,
shape: ShapeCard,
x: number,
y: number,
size: number,
fillColor: string,
) {
ctx.save();
ctx.translate(x, y);
const radius = size / 2;
const shouldFill = fillColor !== 'transparent';
switch (shape.id) {
case 'circle':
drawCircle(
ctx,
0,
0,
radius,
shouldFill ? fillColor : 'transparent',
);
break;
case 'ellipse':
drawEllipse(
ctx,
0,
0,
radius * 0.8,
radius * 0.5,
shouldFill ? fillColor : 'transparent',
);
break;
case 'square':
drawSquare(
ctx,
0,
0,
radius * 1.6,
shouldFill ? fillColor : 'transparent',
);
break;
case 'rectangle':
drawRectangle(
ctx,
0,
0,
radius * 1.8,
radius * 1.2,
shouldFill ? fillColor : 'transparent',
);
break;
case 'obtuse-triangle':
drawTriangle(
ctx,
0,
0,
radius,
'obtuse',
shouldFill ? fillColor : 'transparent',
);
break;
case 'right-triangle':
drawTriangle(
ctx,
0,
0,
radius,
'right',
shouldFill ? fillColor : 'transparent',
);
break;
case 'acute-triangle':
drawTriangle(
ctx,
0,
0,
radius,
'acute',
shouldFill ? fillColor : 'transparent',
);
break;
case 'parallelogram':
drawParallelogram(
ctx,
0,
0,
radius * 1.6,
radius * 1.2,
shouldFill ? fillColor : 'transparent',
);
break;
case 'diamond':
drawDiamond(
ctx,
0,
0,
radius,
shouldFill ? fillColor : 'transparent',
);
break;
case 'trapezoid':
drawTrapezoid(
ctx,
0,
0,
radius * 1.6,
radius * 1.2,
shouldFill ? fillColor : 'transparent',
);
break;
case 'pentagon':
drawPolygon(
ctx,
0,
0,
radius,
5,
shouldFill ? fillColor : 'transparent',
);
break;
case 'hexagon':
drawPolygon(
ctx,
0,
0,
radius,
6,
shouldFill ? fillColor : 'transparent',
);
break;
case 'pentagram':
drawStar(
ctx,
0,
0,
radius,
5,
shouldFill ? fillColor : 'transparent',
);
break;
case 'heart':
drawHeart(
ctx,
0,
0,
radius,
shouldFill ? fillColor : 'transparent',
);
break;
case 'semicircle':
drawSemicircle(
ctx,
0,
0,
radius,
shouldFill ? fillColor : 'transparent',
);
break;
case 'sector':
drawSector(
ctx,
0,
0,
radius,
shouldFill ? fillColor : 'transparent',
);
break;
case 'ring':
drawRing(ctx, 0, 0, radius, shouldFill ? fillColor : 'transparent');
break;
default:
// 默认绘制圆形
drawCircle(
ctx,
0,
0,
radius,
shouldFill ? fillColor : 'transparent',
);
}
ctx.restore();
}