Method _initParticle

packages/particle/src/ParticleEmitter.ts:247–311

(
        p: Particle,
        worldX: number,
        worldY: number,
        worldRotation: number = 0,
        worldScaleX: number = 1,
        worldScaleY: number = 1
    )

    }

    private _initParticle(
        p: Particle,
        worldX: number,
        worldY: number,
        worldRotation: number = 0,
        worldScaleX: number = 1,
        worldScaleY: number = 1
    ): void {
        const config = this.config;

        // 获取形状偏移 | Get shape offset
        const [ox, oy] = this._getShapeOffset();

        // 应用旋转和缩放到发射偏移 | Apply rotation and scale to emission offset
        // 先缩放，再旋转 | Scale first, then rotate
        const scaledOx = ox * worldScaleX;
        const scaledOy = oy * worldScaleY;
        const cos = Math.cos(worldRotation);
        const sin = Math.sin(worldRotation);
        const rotatedOx = scaledOx * cos - scaledOy * sin;
        const rotatedOy = scaledOx * sin + scaledOy * cos;

        // 位置 | Position
        p.x = worldX + rotatedOx;
        p.y = worldY + rotatedOy;

        // 生命时间 | Lifetime
        p.lifetime = randomRange(config.lifetime.min, config.lifetime.max);
        p.age = 0;

        // 速度方向（应用世界旋转）| Velocity direction (apply world rotation)
        const baseDir = config.direction + randomRange(-config.directionSpread / 2, config.directionSpread / 2);
        const dir = baseDir + worldRotation;
        const speed = randomRange(config.speed.min, config.speed.max);

        // 速度也应用缩放（使用平均缩放）| Speed also applies scale (use average scale)
        const avgScale = (worldScaleX + worldScaleY) / 2;
        p.vx = Math.cos(dir) * speed * avgScale;
        p.vy = Math.sin(dir) * speed * avgScale;

        // 加速度（重力）| Acceleration (gravity)
        p.ax = config.gravityX;
        p.ay = config.gravityY;

        // 旋转 | Rotation
        p.rotation = randomRange(config.startRotation.min, config.startRotation.max);
        p.angularVelocity = randomRange(config.angularVelocity.min, config.angularVelocity.max);

        // 缩放（应用世界缩放）| Scale (apply world scale)
        const baseScale = randomRange(config.startScale.min, config.startScale.max);
        p.scaleX = baseScale * worldScaleX;
        p.scaleY = baseScale * worldScaleY;
        p.startScaleX = p.scaleX;
        p.startScaleY = p.scaleY;

        // 颜色 | Color
        p.r = clamp(config.startColor.r + randomRange(-config.startColorVariance.r, config.startColorVariance.r), 0, 1);
        p.g = clamp(config.startColor.g + randomRange(-config.startColorVariance.g, config.startColorVariance.g), 0, 1);