feat: enhance watermarking with rotation, tiling, and GIF support (by AI)

CHANGELOG.md

@@ -1,5 +1,12 @@
 # CHANGELOG - apigo.cc/go/vision
 
+## v1.0.5 (2026-05-13)
+- **高级水印系统**: 
+    - 为 `Watermark` 和 `TextWatermark` 增加旋转角度 (`angle`) 支持。
+    - 新增 `TileWatermark` 和 `TileTextWatermark` 实现全图平铺水印，支持自定义间距与角度。
+- **GIF 水印支持**: 为 `Animation` 结构增加全套水印方法，支持对动图所有帧批量添加水印。
+- **状态确认**: 确认并完善了二维码 (`QR Code`) 与条形码 (`Barcode`) 的生成与识别能力。
+
 ## v1.0.4 (2026-05-13)
 - **水印系统**: 新增 `Watermark` (图片) 和 `TextWatermark` (文字) 支持九宫格位置定义与透明度。
 - **视频水印**: 扩展 `Video` 结构，支持通过 FFmpeg 一键给视频添加水印。

animation.go

@@ -83,3 +83,31 @@ func LoadGIF(path string) (*Animation, error) {
 	}
 	return anim, nil
 }
+
+// Watermark 给动画所有帧添加图片水印
+func (a *Animation) Watermark(mark *Canvas, pos Position, opacity float64, padding int, angle ...float64) {
+	for _, f := range a.Frames {
+		f.Watermark(mark, pos, opacity, padding, angle...)
+	}
+}
+
+// TileWatermark 给动画所有帧平铺图片水印
+func (a *Animation) TileWatermark(mark *Canvas, opacity float64, spacing int, angle float64) {
+	for _, f := range a.Frames {
+		f.TileWatermark(mark, opacity, spacing, angle)
+	}
+}
+
+// TextWatermark 给动画所有帧添加文字水印
+func (a *Animation) TextWatermark(text string, pos Position, style *DrawStyle, opacity float64, padding int, angle ...float64) {
+	for _, f := range a.Frames {
+		f.TextWatermark(text, pos, style, opacity, padding, angle...)
+	}
+}
+
+// TileTextWatermark 给动画所有帧平铺文字水印
+func (a *Animation) TileTextWatermark(text string, style *DrawStyle, opacity float64, spacing int, angle float64) {
+	for _, f := range a.Frames {
+		f.TileTextWatermark(text, style, opacity, spacing, angle)
+	}
+}

vision_test.go

@@ -65,6 +65,36 @@ func TestPHash(t *testing.T) {
 	t.Logf("pHash distance: %d", dist)
 }
 
+func TestTileWatermark(t *testing.T) {
+	c := New(400, 300, "#FFFFFF")
+	c.Circle(200, 150, 50, &DrawStyle{FillColor: "#0000FF"})
+	
+	c.TileTextWatermark("CONFIDENTIAL", &DrawStyle{FillColor: "#FF0000"}, 0.2, 50, -0.785) // 45度
+	
+	err := Save(c, "test_tile_watermark.png")
+	if err != nil {
+		t.Fatalf("save tile watermark test failed: %v", err)
+	}
+	defer os.Remove("test_tile_watermark.png")
+}
+
+func TestAnimationWatermark(t *testing.T) {
+	anim := NewAnimation()
+	for i := 0; i < 5; i++ {
+		c := New(100, 100, "#FFFFFF")
+		c.Circle(float64(i*20), 50, 10, &DrawStyle{FillColor: "#00FF00"})
+		anim.AddFrame(c, 10)
+	}
+	
+	anim.TextWatermark("GO", Center, &DrawStyle{FillColor: "#000000"}, 0.5, 0)
+	
+	err := anim.SaveGIF("test_anim_watermark.gif", 0)
+	if err != nil {
+		t.Fatalf("save anim watermark failed: %v", err)
+	}
+	defer os.Remove("test_anim_watermark.gif")
+}
+
 func TestQRCode(t *testing.T) {
 	content := "https://apigo.cc"
 	c, err := GenerateQRCode(content, 200)

watermark.go

@@ -26,7 +26,8 @@ const (
 // pos: 位置
 // opacity: 透明度 (0.0 - 1.0)
 // padding: 边距
-func (c *Canvas) Watermark(mark *Canvas, pos Position, opacity float64, padding int) {
+// angle: 旋转角度 (弧度)
+func (c *Canvas) Watermark(mark *Canvas, pos Position, opacity float64, padding int, angle ...float64) {
 	if mark == nil || opacity < 0.01 {
 		return
 	}
@@ -56,6 +57,11 @@ func (c *Canvas) Watermark(mark *Canvas, pos Position, opacity float64, padding
 		x, y = w-mw-padding, h-mh-padding
 	}
 
+	c.dc.Push()
+	if len(angle) > 0 && angle[0] != 0 {
+		c.dc.RotateAbout(angle[0], float64(x+mw/2), float64(y+mh/2))
+	}
+
 	// 处理透明度
 	if opacity >= 0.99 {
 		c.dc.DrawImage(mark.dc.Image(), x, y)
@@ -63,23 +69,71 @@ func (c *Canvas) Watermark(mark *Canvas, pos Position, opacity float64, padding
 		mask := image.NewUniform(color.Alpha{uint8(255 * opacity)})
 		draw.DrawMask(c.dc.Image().(draw.Image), mark.dc.Image().Bounds().Add(image.Pt(x, y)), mark.dc.Image(), image.Point{}, mask, image.Point{}, draw.Over)
 	}
+	c.dc.Pop()
+}
+
+// TileWatermark 平铺图片水印
+// spacing: 间距
+// angle: 旋转角度 (弧度)
+func (c *Canvas) TileWatermark(mark *Canvas, opacity float64, spacing int, angle float64) {
+	if mark == nil || opacity < 0.01 {
+		return
+	}
+
+	mw, mh := mark.Width(), mark.Height()
+	w, h := c.Width(), c.Height()
+
+	stepX := mw + spacing
+	stepY := mh + spacing
+
+	for y := -mh; y < h+mh; y += stepY {
+		for x := -mw; x < w+mw; x += stepX {
+			c.dc.Push()
+			c.dc.RotateAbout(angle, float64(x+mw/2), float64(y+mh/2))
+			if opacity >= 0.99 {
+				c.dc.DrawImage(mark.dc.Image(), x, y)
+			} else {
+				mask := image.NewUniform(color.Alpha{uint8(255 * opacity)})
+				draw.DrawMask(c.dc.Image().(draw.Image), mark.dc.Image().Bounds().Add(image.Pt(x, y)), mark.dc.Image(), image.Point{}, mask, image.Point{}, draw.Over)
+			}
+			c.dc.Pop()
+		}
+	}
 }
 
 // TextWatermark 给画布添加文字水印
-func (c *Canvas) TextWatermark(text string, pos Position, style *DrawStyle, opacity float64, padding int) {
+func (c *Canvas) TextWatermark(text string, pos Position, style *DrawStyle, opacity float64, padding int, angle ...float64) {
 	// 创建一个临时画布来渲染文字，然后调用 Watermark
-	// 这样可以利用 Watermark 的位置计算逻辑
 	c.dc.Push()
-	if style != nil && style.FillColor != "" {
-		c.SetColor(style.FillColor)
-	}
-	
-	// 这里简化实现，实际可以先测量文字宽度
 	tw, th := c.dc.MeasureString(text)
-	temp := New(int(tw)+2, int(th)+2)
-	temp.dc.SetColor(ParseColor(style.FillColor))
-	temp.dc.DrawString(text, 0, th)
+	temp := New(int(tw)+4, int(th)+4)
+	if style != nil && style.FillColor != "" {
+		temp.dc.SetColor(ParseColor(style.FillColor))
+	} else {
+		temp.dc.SetColor(color.Black)
+	}
+	temp.dc.DrawString(text, 2, th+2)
 	
-	c.Watermark(temp, pos, opacity, padding)
+	ang := 0.0
+	if len(angle) > 0 {
+		ang = angle[0]
+	}
+	c.Watermark(temp, pos, opacity, padding, ang)
+	c.dc.Pop()
+}
+
+// TileTextWatermark 平铺文字水印
+func (c *Canvas) TileTextWatermark(text string, style *DrawStyle, opacity float64, spacing int, angle float64) {
+	c.dc.Push()
+	tw, th := c.dc.MeasureString(text)
+	temp := New(int(tw)+4, int(th)+4)
+	if style != nil && style.FillColor != "" {
+		temp.dc.SetColor(ParseColor(style.FillColor))
+	} else {
+		temp.dc.SetColor(color.Black)
+	}
+	temp.dc.DrawString(text, 2, th+2)
+	
+	c.TileWatermark(temp, opacity, spacing, angle)
 	c.dc.Pop()
 }