sprites: Speed up: use float64 as often as possible

image.go

@@ -108,9 +108,9 @@ func (l rectVertexQuads) Len() int {
 	return l.Rects.Len()
 }
 
-func (l rectVertexQuads) Vertex(i int) (x0, y0, x1, y1 float32) {
+func (l rectVertexQuads) Vertex(i int) (x0, y0, x1, y1 float64) {
 	ix0, iy0, ix1, iy1 := l.Rects.Points(i)
-	return float32(ix0), float32(iy0), float32(ix1), float32(iy1)
+	return float64(ix0), float64(iy0), float64(ix1), float64(iy1)
 }
 
 // DrawRects draws rectangles on the image.

imageparts.go

@@ -66,12 +66,12 @@ func (w *wholeImage) Src(i int) (x0, y0, x1, y1 int) {
 	return 0, 0, w.width, w.height
 }
 
-func u(x float32, width int) float32 {
+func u(x float64, width int) float64 {
-	return x / float32(internal.NextPowerOf2Int(width))
+	return x / float64(internal.NextPowerOf2Int(width))
 }
 
-func v(y float32, height int) float32 {
+func v(y float64, height int) float64 {
-	return y / float32(internal.NextPowerOf2Int(height))
+	return y / float64(internal.NextPowerOf2Int(height))
 }
 
 type textureQuads struct {
@@ -84,13 +84,13 @@ func (t *textureQuads) Len() int {
 	return t.parts.Len()
 }
 
-func (t *textureQuads) Vertex(i int) (x0, y0, x1, y1 float32) {
+func (t *textureQuads) Vertex(i int) (x0, y0, x1, y1 float64) {
 	ix0, iy0, ix1, iy1 := t.parts.Dst(i)
-	return float32(ix0), float32(iy0), float32(ix1), float32(iy1)
+	return float64(ix0), float64(iy0), float64(ix1), float64(iy1)
 }
 
-func (t *textureQuads) Texture(i int) (u0, v0, u1, v1 float32) {
+func (t *textureQuads) Texture(i int) (u0, v0, u1, v1 float64) {
 	x0, y0, x1, y1 := t.parts.Src(i)
 	w, h := t.width, t.height
-	return u(float32(x0), w), v(float32(y0), h), u(float32(x1), w), v(float32(y1), h)
+	return u(float64(x0), w), v(float64(y0), h), u(float64(x1), w), v(float64(y1), h)
 }

internal/graphics/framebuffer.go

@@ -94,8 +94,8 @@ type Matrix interface {
 
 type TextureQuads interface {
 	Len() int
-	Vertex(i int) (x0, y0, x1, y1 float32)
+	Vertex(i int) (x0, y0, x1, y1 float64)
-	Texture(i int) (u0, v0, u1, v1 float32)
+	Texture(i int) (u0, v0, u1, v1 float64)
 }
 
 func (f *Framebuffer) Fill(c *opengl.Context, r, g, b, a float64) error {
@@ -115,7 +115,7 @@ func (f *Framebuffer) DrawTexture(c *opengl.Context, t *Texture, quads TextureQu
 
 type VertexQuads interface {
 	Len() int
-	Vertex(i int) (x0, y0, x1, y1 float32)
+	Vertex(i int) (x0, y0, x1, y1 float64)
 }
 
 func (f *Framebuffer) DrawRects(c *opengl.Context, r, g, b, a float64, quads VertexQuads) error {

internal/graphics/internal/shader/draw.go

@@ -35,19 +35,19 @@ type Matrix interface {
 
 type TextureQuads interface {
 	Len() int
-	Vertex(i int) (x0, y0, x1, y1 float32)
+	Vertex(i int) (x0, y0, x1, y1 float64)
-	Texture(i int) (u0, v0, u1, v1 float32)
+	Texture(i int) (u0, v0, u1, v1 float64)
 }
 
+// TODO: better name?
+const stride = 4 * 4
+
 var initialized = false
 
 func DrawTexture(c *opengl.Context, texture opengl.Texture, projectionMatrix *[4][4]float64, quads TextureQuads, geo Matrix, color Matrix) error {
 	// TODO: WebGL doesn't seem to have Check gl.MAX_ELEMENTS_VERTICES or gl.MAX_ELEMENTS_INDICES so far.
 	// Let's use them to compare to len(quads) in the future.
 
-	// TODO: Unify stride or other consts
-	const stride = 4 * 4
-
 	if !initialized {
 		if err := initialize(c); err != nil {
 			return err
@@ -73,10 +73,10 @@ func DrawTexture(c *opengl.Context, texture opengl.Texture, projectionMatrix *[4
 			continue
 		}
 		vertices = append(vertices,
-			x0, y0, u0, v0,
+			float32(x0), float32(y0), float32(u0), float32(v0),
-			x1, y0, u1, v0,
+			float32(x1), float32(y0), float32(u1), float32(v0),
-			x0, y1, u0, v1,
+			float32(x0), float32(y1), float32(u0), float32(v1),
-			x1, y1, u1, v1,
+			float32(x1), float32(y1), float32(u1), float32(v1),
 		)
 	}
 	if len(vertices) == 0 {
@@ -89,7 +89,7 @@ func DrawTexture(c *opengl.Context, texture opengl.Texture, projectionMatrix *[4
 
 type VertexQuads interface {
 	Len() int
-	Vertex(i int) (x0, y0, x1, y1 float32)
+	Vertex(i int) (x0, y0, x1, y1 float64)
 }
 
 func max(a, b float32) float32 {
@@ -99,9 +99,9 @@ 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 {
+var vertices = make([]float32, 0, stride*quadsMaxNum)
-	const stride = 4 * 4
 
+func DrawRects(c *opengl.Context, projectionMatrix *[4][4]float64, r, g, b, a float64, quads VertexQuads) error {
 	if !initialized {
 		if err := initialize(c); err != nil {
 			return err
@@ -116,17 +116,17 @@ func DrawRects(c *opengl.Context, projectionMatrix *[4][4]float64, r, g, b, a fl
 	f := useProgramRect(c, glMatrix(projectionMatrix), r, g, b, a)
 	defer f.FinishProgram()
 
-	vertices := make([]float32, 0, stride*quads.Len())
+	vertices := vertices[0:0]
 	for i := 0; i < quads.Len(); i++ {
 		x0, y0, x1, y1 := quads.Vertex(i)
 		if x0 == x1 || y0 == y1 {
 			continue
 		}
 		vertices = append(vertices,
-			x0, y0, 0, 0,
+			float32(x0), float32(y0), 0, 0,
-			x1, y0, 1, 0,
+			float32(x1), float32(y0), 1, 0,
-			x0, y1, 0, 1,
+			float32(x0), float32(y1), 0, 1,
-			x1, y1, 1, 1,
+			float32(x1), float32(y1), 1, 1,
 		)
 	}
 	if len(vertices) == 0 {