156 lines
3.6 KiB
Go
156 lines
3.6 KiB
Go
package drawhelper
|
||
|
||
import (
|
||
"image"
|
||
"image/color"
|
||
|
||
"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 int, radius float64, 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 := float64(0)
|
||
y := float64(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+int(x), y0+int(y), r8, g8, b8, a8)
|
||
DrawPointIfInBounds(img, bounds, x0+int(x), y0-int(y), r8, g8, b8, a8)
|
||
DrawPointIfInBounds(img, bounds, x0-int(x), y0+int(y), r8, g8, b8, a8)
|
||
DrawPointIfInBounds(img, bounds, x0-int(x), y0-int(y), r8, g8, b8, a8)
|
||
DrawPointIfInBounds(img, bounds, x0+int(y), y0+int(x), r8, g8, b8, a8)
|
||
DrawPointIfInBounds(img, bounds, x0+int(y), y0-int(x), r8, g8, b8, a8)
|
||
DrawPointIfInBounds(img, bounds, x0-int(y), y0+int(x), r8, g8, b8, a8)
|
||
DrawPointIfInBounds(img, bounds, x0-int(y), y0-int(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
|
||
}
|
||
}
|