diff --git a/image.go b/image.go
index 37b4c3168..4db945810 100644
--- a/image.go
+++ b/image.go
@@ -103,7 +103,7 @@ func (i *Image) DrawRect(x, y, width, height int, clr color.Color) error {
 // DrawRects draws rectangles on the image.
 func (i *Image) DrawRects(rects Rects) (err error) {
 	ui.Use(func(c *opengl.Context) {
-		err = i.framebuffer.DrawRects(c, &rectVertexQuads{rects})
+		err = i.framebuffer.DrawRects(c, rects)
 	})
 	return
 }
diff --git a/internal/graphics/framebuffer.go b/internal/graphics/framebuffer.go
index 39777acee..9707a53d0 100644
--- a/internal/graphics/framebuffer.go
+++ b/internal/graphics/framebuffer.go
@@ -114,16 +114,16 @@ func (f *Framebuffer) DrawTexture(c *opengl.Context, t *Texture, quads TextureQu
 	return shader.DrawTexture(c, t.native, p, quads, geo, clr)
 }
 
-type VertexQuads interface {
+type Rects interface {
 	Len() int
-	Vertex(i int) (x0, y0, x1, y1 int)
+	Rect(i int) (x, y, width, height int)
 	Color(i int) color.Color
 }
 
-func (f *Framebuffer) DrawRects(c *opengl.Context, quads VertexQuads) error {
+func (f *Framebuffer) DrawRects(c *opengl.Context, rects Rects) error {
 	if err := f.setAsViewport(c); err != nil {
 		return err
 	}
 	p := f.projectionMatrix()
-	return shader.DrawRects(c, p, quads)
+	return shader.DrawRects(c, p, rects)
 }
diff --git a/internal/graphics/internal/shader/draw.go b/internal/graphics/internal/shader/draw.go
index 3fcc3cbd0..7c6bb77f1 100644
--- a/internal/graphics/internal/shader/draw.go
+++ b/internal/graphics/internal/shader/draw.go
@@ -89,20 +89,13 @@ func DrawTexture(c *opengl.Context, texture opengl.Texture, projectionMatrix *[4
 	return nil
 }
 
-type VertexQuads interface {
+type Rects interface {
 	Len() int
-	Vertex(i int) (x0, y0, x1, y1 int)
+	Rect(i int) (x, y, width, height int)
 	Color(i int) color.Color
 }
 
-func max(a, b float32) float32 {
-	if a < b {
-		return b
-	}
-	return a
-}
-
-func DrawRects(c *opengl.Context, projectionMatrix *[4][4]float64, quads VertexQuads) error {
+func DrawRects(c *opengl.Context, projectionMatrix *[4][4]float64, rects Rects) error {
 	if !initialized {
 		if err := initialize(c); err != nil {
 			return err
@@ -110,7 +103,7 @@ func DrawRects(c *opengl.Context, projectionMatrix *[4][4]float64, quads VertexQ
 		initialized = true
 	}
 
-	if quads.Len() == 0 {
+	if rects.Len() == 0 {
 		return nil
 	}
 
@@ -119,12 +112,13 @@ func DrawRects(c *opengl.Context, projectionMatrix *[4][4]float64, quads VertexQ
 
 	vertices := vertices[0:0]
 	num := 0
-	for i := 0; i < quads.Len(); i++ {
-		x0, y0, x1, y1 := quads.Vertex(i)
-		if x0 == x1 || y0 == y1 {
+	for i := 0; i < rects.Len(); i++ {
+		x, y, w, h := rects.Rect(i)
+		if w == 0 || h == 0 {
 			continue
 		}
-		r, g, b, a := quads.Color(i).RGBA()
+		x0, y0, x1, y1 := x, y, x+w, y+h
+		r, g, b, a := rects.Color(i).RGBA()
 		vertices = append(vertices,
 			int16(x0), int16(y0), int16(r), int16(g), int16(b), int16(a),
 			int16(x1), int16(y0), int16(r), int16(g), int16(b), int16(a),
diff --git a/shapes.go b/shapes.go
index be2bc3870..1b98eef27 100644
--- a/shapes.go
+++ b/shapes.go
@@ -42,20 +42,3 @@ func (r *rect) Rect(i int) (x, y, width, height int) {
 func (r *rect) Color(i int) color.Color {
 	return r.color
 }
-
-type rectVertexQuads struct {
-	Rects
-}
-
-func (l *rectVertexQuads) Len() int {
-	return l.Rects.Len()
-}
-
-func (l *rectVertexQuads) Vertex(i int) (x0, y0, x1, y1 int) {
-	x, y, width, height := l.Rects.Rect(i)
-	return x, y, x + width, y + height
-}
-
-func (l *rectVertexQuads) Color(i int) color.Color {
-	return l.Rects.Color(i)
-}