Remove graphics.Context.DrawRect

example/game/rects/rects.go

@@ -25,33 +25,41 @@ import (
 	"github.com/hajimehoshi/go.ebiten/graphics"
 	"github.com/hajimehoshi/go.ebiten/graphics/matrix"
 	"image/color"
+	"math"
 	"math/rand"
 	"time"
 )
 
 type Rects struct {
-	rectsTexture graphics.Texture
-	rect         *graphics.Rect
-	rectColor    *color.RGBA
+	rectTexture        graphics.Texture
+	rectTextureInited  bool
+	rectsTexture       graphics.Texture
+	rectsTextureInited bool
+	rectBounds         *graphics.Rect
+	rectColor          *color.RGBA
 }
 
 func New() *Rects {
 	return &Rects{
-		rect:      &graphics.Rect{},
-		rectColor: &color.RGBA{},
+		rectTextureInited:  false,
+		rectsTextureInited: false,
+		rectBounds:         &graphics.Rect{},
+		rectColor:          &color.RGBA{},
 	}
 }
 
 func (game *Rects) Init(tf graphics.TextureFactory) {
-	// TODO: fix
+	game.rectTexture = tf.NewTexture(16, 16)
 	game.rectsTexture = tf.NewTexture(256, 240)
 }
 
 func (game *Rects) Update(context ebiten.GameContext) {
-	game.rect.X = rand.Intn(context.ScreenWidth())
-	game.rect.Y = rand.Intn(context.ScreenHeight())
-	game.rect.Width = rand.Intn(context.ScreenWidth() - game.rect.X)
-	game.rect.Height = rand.Intn(context.ScreenHeight() - game.rect.Y)
+	game.rectBounds.X = rand.Intn(context.ScreenWidth())
+	game.rectBounds.Y = rand.Intn(context.ScreenHeight())
+	game.rectBounds.Width =
+		rand.Intn(context.ScreenWidth() - game.rectBounds.X)
+	game.rectBounds.Height =
+		rand.Intn(context.ScreenHeight() - game.rectBounds.Y)
 
 	game.rectColor.R = uint8(rand.Intn(256))
 	game.rectColor.G = uint8(rand.Intn(256))
@@ -59,10 +67,46 @@ func (game *Rects) Update(context ebiten.GameContext) {
 	game.rectColor.A = uint8(rand.Intn(256))
 }
 
-func (game *Rects) Draw(g graphics.Context) {
-	g.SetOffscreen(game.rectsTexture.ID())
+func (game *Rects) rectGeometryMatrix() matrix.Geometry {
+	geometryMatrix := matrix.IdentityGeometry()
+	scaleX := float64(game.rectBounds.Width) /
+		float64(game.rectTexture.Width())
+	scaleY := float64(game.rectBounds.Height) /
+		float64(game.rectTexture.Height())
+	geometryMatrix.Scale(scaleX, scaleY)
+	geometryMatrix.Translate(
+		float64(game.rectBounds.X), float64(game.rectBounds.Y))
+	return geometryMatrix
+}
 
-	g.DrawRect(*game.rect, game.rectColor)
+func (game *Rects) rectColorMatrix() matrix.Color {
+	colorMatrix := matrix.IdentityColor()
+	colorMatrix.Elements[0][0] =
+		float64(game.rectColor.R) / float64(math.MaxUint8)
+	colorMatrix.Elements[1][1] =
+		float64(game.rectColor.G) / float64(math.MaxUint8)
+	colorMatrix.Elements[2][2] =
+		float64(game.rectColor.B) / float64(math.MaxUint8)
+	colorMatrix.Elements[3][3] =
+		float64(game.rectColor.A) / float64(math.MaxUint8)
+	return colorMatrix
+}
+
+func (game *Rects) Draw(g graphics.Context) {
+	if !game.rectTextureInited {
+		g.SetOffscreen(game.rectTexture.ID())
+		g.Fill(&color.White)
+		game.rectTextureInited = true
+	}
+
+	g.SetOffscreen(game.rectsTexture.ID())
+	if !game.rectsTextureInited {
+		g.Fill(&color.RGBA{0, 0, 0, 255})
+		game.rectsTextureInited = true
+	}
+	g.DrawTexture(game.rectTexture.ID(),
+		game.rectGeometryMatrix(),
+		game.rectColorMatrix())
 
 	g.SetOffscreen(g.Screen().ID())
 	g.DrawTexture(game.rectsTexture.ID(),

graphics/graphics.go

@@ -43,7 +43,6 @@ type Context interface {
 	Screen() Texture
 	Clear()
 	Fill(clr color.Color)
-	DrawRect(rect Rect, clr color.Color)
 	DrawTexture(textureID TextureID,
 		geometryMatrix matrix.Geometry,
 		colorMatrix matrix.Color)

graphics/matrix/geometry.go

@@ -67,12 +67,12 @@ func (matrix *Geometry) Translate(tx, ty float64) {
 }
 
 func (matrix *Geometry) Scale(x, y float64) {
-	matrix.Elements[0][0] = x * matrix.Elements[0][0]
-	matrix.Elements[0][1] = x * matrix.Elements[0][1]
-	matrix.Elements[0][2] = x * matrix.Elements[0][2]
-	matrix.Elements[1][0] = y * matrix.Elements[1][0]
-	matrix.Elements[1][1] = y * matrix.Elements[1][1]
-	matrix.Elements[1][2] = y * matrix.Elements[1][2]
+	matrix.Elements[0][0] *= x
+	matrix.Elements[0][1] *= x
+	matrix.Elements[0][2] *= x
+	matrix.Elements[1][0] *= y
+	matrix.Elements[1][1] *= y
+	matrix.Elements[1][2] *= y
 }
 
 func (matrix *Geometry) Rotate(theta float64) {

graphics/opengl/context.go

@@ -91,53 +91,6 @@ func (context *Context) Fill(clr color.Color) {
 	C.glClear(C.GL_COLOR_BUFFER_BIT)
 }
 
-func (context *Context) DrawRect(rect graphics.Rect, clr color.Color) {
-	width := float32(context.currentOffscreen.Width())
-	height := float32(context.currentOffscreen.Height())
-	textureWidth := float32(clp2(uint64(width)))
-	textureHeight := float32(clp2(uint64(height)))
-
-	// Normalize the coord between -1.0 and 1.0.
-	x1 := float32(rect.X)/textureWidth*2.0 - 1.0
-	x2 := float32(rect.X+rect.Width)/textureHeight*2.0 - 1.0
-	y1 := float32(rect.Y)/textureHeight*2.0 - 1.0
-	y2 := float32(rect.Y+rect.Height)/textureHeight*2.0 - 1.0
-	vertex := [...]float32{
-		x1, y1,
-		x2, y1,
-		x1, y2,
-		x2, y2,
-	}
-
-	origR, origG, origB, origA := clr.RGBA()
-	max := float32(math.MaxUint16)
-	r := float32(origR) / max
-	g := float32(origG) / max
-	b := float32(origB) / max
-	a := float32(origA) / max
-	color := [...]float32{
-		r, g, b, a,
-		r, g, b, a,
-		r, g, b, a,
-		r, g, b, a,
-	}
-
-	C.glUseProgram(0)
-	C.glDisable(C.GL_TEXTURE_2D)
-	C.glEnableClientState(C.GL_VERTEX_ARRAY)
-	C.glEnableClientState(C.GL_COLOR_ARRAY)
-	C.glVertexPointer(2, C.GL_FLOAT, C.GL_FALSE, unsafe.Pointer(&vertex[0]))
-	C.glColorPointer(4, C.GL_FLOAT, C.GL_FALSE, unsafe.Pointer(&color[0]))
-	C.glDrawArrays(C.GL_TRIANGLE_STRIP, 0, 4)
-	C.glDisableClientState(C.GL_COLOR_ARRAY)
-	C.glDisableClientState(C.GL_VERTEX_ARRAY)
-	C.glEnable(C.GL_TEXTURE_2D)
-
-	if glError := C.glGetError(); glError != C.GL_NO_ERROR {
-		panic("OpenGL error")
-	}
-}
-
 func (context *Context) DrawTexture(
 	textureID graphics.TextureID,
 	geometryMatrix matrix.Geometry, colorMatrix matrix.Color) {