From 9e757c4fc9cba4610b4b9c2a887e4bd042e8fee7 Mon Sep 17 00:00:00 2001
From: Sander Schobers <sander@schobers.eu>
Date: Fri, 27 Dec 2019 13:57:16 +0100
Subject: [PATCH] Added cabinet projection to tileblueprint.

---
 cmd/tileblueprint/tileblueprint.go | 91 ++++++++++++++++++++++++------
 1 file changed, 74 insertions(+), 17 deletions(-)

diff --git a/cmd/tileblueprint/tileblueprint.go b/cmd/tileblueprint/tileblueprint.go
index 73e9690..35957fc 100644
--- a/cmd/tileblueprint/tileblueprint.go
+++ b/cmd/tileblueprint/tileblueprint.go
@@ -19,45 +19,102 @@ func main() {
 	}
 }
 
+type projection interface {
+	tile() (width float64, height float64)
+	draw(gc *draw2dimg.GraphicContext, x, y, w, h, scale float64, p palette)
+}
+
+type cabinet struct {
+}
+
+func (cabinet) tile() (float64, float64) {
+	return 150, 140
+}
+
+func (cabinet) draw(gc *draw2dimg.GraphicContext, x, y, w, h, scale float64, p palette) {
+	dw := func(d float64) float64 { return (d / w) * w * scale }
+	dh := func(d float64) float64 { return (d / h) * h * scale }
+	gc.MoveTo(x, y+dh(40))
+	gc.LineTo(x, y+h)
+	gc.LineTo(x+dw(100), y+h)
+	gc.LineTo(x+w, y+dh(100))
+	gc.LineTo(x+w, y)
+	gc.LineTo(x+dw(100), y+dh(40))
+	gc.LineTo(x+dw(100), y+h)
+	gc.MoveTo(x+dw(100), y+dh(40))
+	gc.LineTo(x, y+dh(40))
+	gc.LineTo(x+dw(50), y)
+	gc.LineTo(x+w, y)
+	gc.LineTo(x+dw(100), y+dh(40))
+	gc.SetStrokeColor(p.tile)
+	gc.Stroke()
+}
+
+type isometric struct {
+}
+
+func (isometric) tile() (float64, float64) {
+	return 140, 200
+}
+
+type palette struct {
+	margin color.Color
+	tile   color.Color
+}
+
+func (isometric) draw(gc *draw2dimg.GraphicContext, x, y, w, h, scale float64, p palette) {
+	gc.MoveTo(x, y+.25*h)
+	gc.LineTo(x, y+.75*h)
+	gc.LineTo(x+.5*w, y+h)
+	gc.LineTo(x+w, y+.75*h)
+	gc.LineTo(x+w, y+.25*h)
+	gc.LineTo(x+.5*w, y+.5*h)
+	gc.LineTo(x, y+.25*h)
+	gc.LineTo(x+.5*w, y)
+	gc.LineTo(x+w, y+.25*h)
+	gc.MoveTo(x+.5*w, y+.5*h)
+	gc.LineTo(x+.5*w, y+h)
+	gc.SetStrokeColor(p.tile)
+	gc.Stroke()
+}
+
 func run() error {
 	var dpi int
+	var proj string
 	flag.IntVar(&dpi, "dpi", 300, "dpi")
+	flag.StringVar(&proj, "projection", "", "projection: either isometric (default) or cabinet")
 	flag.Parse()
 	path := flag.Arg(0)
 	if path == "" {
 		return errors.New("no output path specified")
 	}
 
+	var p projection
+	switch proj {
+	case "cabinet":
+		p = cabinet{}
+	default:
+		p = isometric{}
+	}
+
 	bounds := image.Rect(0, 0, dpi*827/100, dpi*1169/100)
 	scale := float64(dpi) / 100
 	margin := 5. * scale
-	tileWidth, tileHeight := 140.*scale, 200.*scale
+	tileWidth, tileHeight := p.tile()
+	tileWidth, tileHeight = tileWidth*scale, tileHeight*scale
 	tileOffsetWidth, tileOffsetHeight := tileWidth+4.*margin, tileHeight+4.*margin
 	im := image.NewRGBA(bounds)
 	gc := draw2dimg.NewGraphicContext(im)
-	marginColor := color.Gray{Y: 63}
-	tileColor := color.Gray{Y: 127}
 	gc.SetLineWidth(1)
+	palette := palette{margin: color.Gray{Y: 63}, tile: color.Gray{Y: 127}}
 	for y := 0.; y < float64(bounds.Max.Y)-tileOffsetHeight; y += tileOffsetHeight {
 		for x := 0.; x < float64(bounds.Max.X)-tileOffsetWidth; x += tileOffsetWidth {
 			draw2dkit.Rectangle(gc, x+margin-1, y+margin-1, x+tileOffsetWidth-margin, y+tileOffsetHeight-margin)
-			gc.SetStrokeColor(marginColor)
+			gc.SetStrokeColor(palette.margin)
 			gc.Stroke()
 
 			tileX, tileY := x+2*margin-.5, y+2*margin-.5
-			gc.MoveTo(tileX, tileY+.25*tileHeight)
-			gc.LineTo(tileX, tileY+.75*tileHeight)
-			gc.LineTo(tileX+.5*tileWidth, tileY+tileHeight)
-			gc.LineTo(tileX+tileWidth, tileY+.75*tileHeight)
-			gc.LineTo(tileX+tileWidth, tileY+.25*tileHeight)
-			gc.LineTo(tileX+.5*tileWidth, tileY+.5*tileHeight)
-			gc.LineTo(tileX, tileY+.25*tileHeight)
-			gc.LineTo(tileX+.5*tileWidth, tileY)
-			gc.LineTo(tileX+tileWidth, tileY+.25*tileHeight)
-			gc.MoveTo(tileX+.5*tileWidth, tileY+.5*tileHeight)
-			gc.LineTo(tileX+.5*tileWidth, tileY+tileHeight)
-			gc.SetStrokeColor(tileColor)
-			gc.Stroke()
+			p.draw(gc, tileX, tileY, tileWidth, tileHeight, scale, palette)
 		}
 	}
 	return draw2dimg.SaveToPngFile(path, im)