refactor: 移除旧的绘制模块，添加新的绘制辅助函数和精灵管理功能，增强图形处理能力。

drawhelper/draw.go

@@ -0,0 +1,156 @@
+package drawhelper
+
+import (
+	"image"
+	"image/color"
+	"log"
+
+	"git.lxtend.com/lixiangwuxian/imagedd/util"
+)
+
+// 辅助函数：在图像上绘制宽线条
+func DrawThickLineOnImage(img *image.RGBA, x0, y0, x1, y1, width int, color color.Color) {
+	// 获取颜色分量
+	r, g, b, a := color.RGBA()
+	r8, g8, b8, a8 := uint8(r>>8), uint8(g>>8), uint8(b>>8), uint8(a>>8)
+
+	bounds := img.Bounds()
+
+	// 使用Bresenham算法绘制线段作为中心线
+	dx := util.Abs(x1 - x0)
+	dy := util.Abs(y1 - y0)
+	sx, sy := 1, 1
+	if x0 >= x1 {
+		sx = -1
+	}
+	if y0 >= y1 {
+		sy = -1
+	}
+	err := dx - dy
+
+	// 计算线宽的一半（向下取整）
+	halfWidth := width / 2
+
+	// 绘制线条
+	x, y := x0, y0
+	for {
+		// 绘制宽线条（在中心点周围绘制圆形区域）
+		for wy := -halfWidth; wy <= halfWidth; wy++ {
+			for wx := -halfWidth; wx <= halfWidth; wx++ {
+				// 只绘制在线宽范围内的点（圆形区域）
+				if wx*wx+wy*wy <= halfWidth*halfWidth {
+					DrawPointIfInBounds(img, bounds, x+wx, y+wy, r8, g8, b8, a8)
+				}
+			}
+		}
+
+		if x == x1 && y == y1 {
+			break
+		}
+
+		e2 := 2 * err
+		if e2 > -dy {
+			err -= dy
+			x += sx
+		}
+		if e2 < dx {
+			err += dx
+			y += sy
+		}
+	}
+}
+
+// 辅助函数：在图像上绘制线段
+func DrawLineOnImage(img *image.RGBA, x0, y0, x1, y1 int, color color.Color) {
+	r, g, b, a := color.RGBA()
+	r8, g8, b8, a8 := uint8(r>>8), uint8(g>>8), uint8(b>>8), uint8(a>>8)
+
+	// 输出颜色值用于调试
+	log.Printf("绘制线条: 颜色 RGBA(%d,%d,%d,%d)", r8, g8, b8, a8)
+
+	bounds := img.Bounds()
+
+	// 使用Bresenham算法绘制线段
+	dx := util.Abs(x1 - x0)
+	dy := util.Abs(y1 - y0)
+	sx, sy := 1, 1
+	if x0 >= x1 {
+		sx = -1
+	}
+	if y0 >= y1 {
+		sy = -1
+	}
+	err := dx - dy
+
+	for {
+		// 绘制点，但只在有效范围内
+		DrawPointIfInBounds(img, bounds, x0, y0, r8, g8, b8, a8)
+
+		if x0 == x1 && y0 == y1 {
+			break
+		}
+
+		e2 := 2 * err
+		if e2 > -dy {
+			err -= dy
+			x0 += sx
+		}
+		if e2 < dx {
+			err += dx
+			y0 += sy
+		}
+	}
+}
+
+// 辅助函数：在图像上绘制圆
+func DrawCircleOnImage(img *image.RGBA, x0, y0, radius int, color color.Color) {
+	r, g, b, a := color.RGBA()
+	r8, g8, b8, a8 := uint8(r>>8), uint8(g>>8), uint8(b>>8), uint8(a>>8)
+
+	// 使用Bresenham算法绘制圆
+	x := 0
+	y := radius
+	d := 3 - 2*radius
+
+	bounds := img.Bounds()
+
+	for {
+		// 绘制8个对称点，但只在图像范围内
+		DrawPointIfInBounds(img, bounds, x0+x, y0+y, r8, g8, b8, a8)
+		DrawPointIfInBounds(img, bounds, x0+x, y0-y, r8, g8, b8, a8)
+		DrawPointIfInBounds(img, bounds, x0-x, y0+y, r8, g8, b8, a8)
+		DrawPointIfInBounds(img, bounds, x0-x, y0-y, r8, g8, b8, a8)
+		DrawPointIfInBounds(img, bounds, x0+y, y0+x, r8, g8, b8, a8)
+		DrawPointIfInBounds(img, bounds, x0+y, y0-x, r8, g8, b8, a8)
+		DrawPointIfInBounds(img, bounds, x0-y, y0+x, r8, g8, b8, a8)
+		DrawPointIfInBounds(img, bounds, x0-y, y0-x, r8, g8, b8, a8)
+
+		if d < 0 {
+			d += 4*x + 6
+		} else {
+			d += 4*(x-y) + 10
+			y--
+		}
+		x++
+
+		if x > y {
+			break
+		}
+	}
+}
+
+// 辅助函数：在图像上设置像素，但只在有效范围内
+func DrawPointIfInBounds(img *image.RGBA, bounds image.Rectangle, x, y int, r, g, b, a uint8) {
+	if x >= bounds.Min.X && x < bounds.Max.X && y >= bounds.Min.Y && y < bounds.Max.Y {
+		// 记录绘制的像素位置和颜色，便于调试
+		if (r > 0 || g > 0 || b > 0) && a > 0 {
+			log.Printf("绘制像素: (%d,%d) RGBA(%d,%d,%d,%d)", x, y, r, g, b, a)
+		}
+
+		idx := (y-bounds.Min.Y)*img.Stride + (x-bounds.Min.X)*4
+		img.Pix[idx] = r
+		img.Pix[idx+1] = g
+		img.Pix[idx+2] = b
+		img.Pix[idx+3] = a
+	}
+}