Add Rect.Color

example/shapes/main.go

@@ -28,6 +28,7 @@ const (
 )
 
 var rectsToDraw = make([]image.Rectangle, 100)
+var colors = make([]color.NRGBA, 100)
 
 func min(a, b int) int {
 	if a < b {
@@ -48,22 +49,31 @@ func init() {
 		x0, x1 := rand.Intn(screenWidth), rand.Intn(screenWidth)
 		y0, y1 := rand.Intn(screenHeight), rand.Intn(screenHeight)
 		rectsToDraw[i] = image.Rect(min(x0, x1), min(y0, y1), max(x0, x1), max(y0, y1))
+		r, g, b, a := uint8(rand.Intn(0xff)), uint8(rand.Intn(0xff)), uint8(rand.Intn(0xff)), uint8(rand.Intn(0xff))
+		colors[i] = color.NRGBA{r, g, b, a}
 	}
 }
 
-type rects []image.Rectangle
+type rects struct {
+	rects  []image.Rectangle
+	colors []color.NRGBA
+}
 
 func (r rects) Len() int {
-	return len(r)
+	return len(r.rects)
 }
 
 func (r rects) Points(i int) (x0, y0, x1, y1 int) {
-	rect := &r[i]
+	rect := &r.rects[i]
 	return rect.Min.X, rect.Min.Y, rect.Max.X, rect.Max.Y
 }
 
+func (r rects) Color(i int) color.Color {
+	return r.colors[i]
+}
+
 func update(screen *ebiten.Image) error {
-	screen.DrawRects(color.NRGBA{0x80, 0x80, 0xff, 0x80}, rects(rectsToDraw))
+	screen.DrawRects(&rects{rectsToDraw, colors})
 	return nil
 }
 

image.go

@@ -98,6 +98,7 @@ func (i *Image) DrawImage(image *Image, options *DrawImageOptions) (err error) {
 type Rects interface {
 	Len() int
 	Points(i int) (x0, y0, x1, y1 int)
+	Color(i int) color.Color
 }
 
 type rectVertexQuads struct {
@@ -113,13 +114,16 @@ func (l rectVertexQuads) Vertex(i int) (x0, y0, x1, y1 float64) {
 	return float64(ix0), float64(iy0), float64(ix1), float64(iy1)
 }
 
+func (l rectVertexQuads) Color(i int) color.Color {
+	return l.Rects.Color(i)
+}
+
 // DrawRects draws rectangles on the image.
 //
 // NOTE: This method is experimental.
-func (i *Image) DrawRects(clr color.Color, rects Rects) (err error) {
+func (i *Image) DrawRects(rects Rects) (err error) {
-	r, g, b, a := internal.RGBA(clr)
 	ui.Use(func(c *opengl.Context) {
-		err = i.framebuffer.DrawRects(c, r, g, b, a, &rectVertexQuads{rects})
+		err = i.framebuffer.DrawRects(c, &rectVertexQuads{rects})
 	})
 	return
 }

internal/graphics/framebuffer.go

@@ -18,6 +18,7 @@ import (
 	"github.com/hajimehoshi/ebiten/internal"
 	"github.com/hajimehoshi/ebiten/internal/graphics/internal/shader"
 	"github.com/hajimehoshi/ebiten/internal/opengl"
+	"image/color"
 )
 
 func orthoProjectionMatrix(left, right, bottom, top int) *[4][4]float64 {
@@ -116,12 +117,13 @@ func (f *Framebuffer) DrawTexture(c *opengl.Context, t *Texture, quads TextureQu
 type VertexQuads interface {
 	Len() int
 	Vertex(i int) (x0, y0, x1, y1 float64)
+	Color(i int) color.Color
 }
 
-func (f *Framebuffer) DrawRects(c *opengl.Context, r, g, b, a float64, quads VertexQuads) error {
+func (f *Framebuffer) DrawRects(c *opengl.Context, quads VertexQuads) error {
 	if err := f.setAsViewport(c); err != nil {
 		return err
 	}
 	p := f.projectionMatrix()
-	return shader.DrawRects(c, p, r, g, b, a, quads)
+	return shader.DrawRects(c, p, quads)
 }

internal/graphics/internal/shader/draw.go

@@ -17,7 +17,9 @@ package shader
 import (
 	"errors"
 	"fmt"
+	"github.com/hajimehoshi/ebiten/internal"
 	"github.com/hajimehoshi/ebiten/internal/opengl"
+	"image/color"
 )
 
 func glMatrix(m *[4][4]float64) []float32 {
@@ -91,6 +93,7 @@ func DrawTexture(c *opengl.Context, texture opengl.Texture, projectionMatrix *[4
 type VertexQuads interface {
 	Len() int
 	Vertex(i int) (x0, y0, x1, y1 float64)
+	Color(i int) color.Color
 }
 
 func max(a, b float32) float32 {
@@ -100,7 +103,7 @@ func max(a, b float32) float32 {
 	return a
 }
 
-func DrawRects(c *opengl.Context, projectionMatrix *[4][4]float64, r, g, b, a float64, quads VertexQuads) error {
+func DrawRects(c *opengl.Context, projectionMatrix *[4][4]float64, quads VertexQuads) error {
 	if !initialized {
 		if err := initialize(c); err != nil {
 			return err
@@ -122,6 +125,7 @@ func DrawRects(c *opengl.Context, projectionMatrix *[4][4]float64, r, g, b, a fl
 		if x0 == x1 || y0 == y1 {
 			continue
 		}
+		r, g, b, a := internal.RGBA(quads.Color(i))
 		vertices = append(vertices,
 			float32(x0), float32(y0), float32(r), float32(g), float32(b), float32(a),
 			float32(x1), float32(y0), float32(r), float32(g), float32(b), float32(a),