Rename layouts.go -> contract.go

layouts/contract.go

@@ -0,0 +1,95 @@
+package layouts
+
+import "image"
+import "git.tebibyte.media/tomo/tomo"
+
+// Contract is a layout that arranges boxes in a simple row or column according
+// to their minimum sizes.
+type Contract bool
+
+// ContractVertical is a vertical contracted layout.
+const ContractVertical Contract = true
+
+// ContractHorizontal is a horizontal contracted layout.
+const ContractHorizontal Contract = false
+
+func (contract Contract) MinimumSize (hints tomo.LayoutHints, boxes []tomo.Box) image.Point {
+	if contract.v() {
+		dot := image.Point { }
+		for _, box := range boxes {
+			minimum := box.MinimumSize()
+			dot.Y += minimum.Y
+			if dot.X < minimum.X {
+				dot.X = minimum.X
+			}
+		}
+		dot.Y += hints.Gap.Y * (len(boxes) - 1)
+		return dot
+	} else {
+		dot := image.Point { }
+		for _, box := range boxes {
+			minimum := box.MinimumSize()
+			dot.X += minimum.X
+			if dot.Y < minimum.Y {
+				dot.Y = minimum.Y
+			}
+		}
+		dot.X += hints.Gap.X * (len(boxes) - 1)
+		return dot
+	}
+}
+
+func (contract Contract) Arrange (hints tomo.LayoutHints, boxes []tomo.Box) {
+	if contract.v() {
+		dot := hints.Bounds.Min
+		for index, box := range boxes {
+			if index > 0 { dot.Y += hints.Gap.Y }
+			minimum := box.MinimumSize()
+			box.SetBounds(image.Rectangle {
+				Min: dot,
+				Max: dot.Add(image.Pt(hints.Bounds.Dx(), minimum.Y)),
+			})
+			dot.Y += minimum.Y
+		}
+		
+		height := dot.Y - hints.Bounds.Min.Y
+		offset := 0
+		
+		switch hints.AlignY {
+		case tomo.AlignMiddle:
+			offset = (hints.Bounds.Dy() - height) / 2
+		case tomo.AlignEnd:
+			offset = hints.Bounds.Dy() - height
+		}
+		for _, box := range boxes {
+			box.SetBounds(box.Bounds().Add(image.Pt(0, offset)))
+		}
+	} else {
+		dot := hints.Bounds.Min
+		for index, box := range boxes {
+			if index > 0 { dot.X += hints.Gap.X }
+			minimum := box.MinimumSize()
+			box.SetBounds(image.Rectangle {
+				Min: dot,
+				Max: dot.Add(image.Pt(minimum.X, hints.Bounds.Dy())),
+			})
+			dot.X += minimum.X
+		}
+
+		width  := dot.X - hints.Bounds.Min.X
+		offset := 0
+		
+		switch hints.AlignX {
+		case tomo.AlignMiddle:
+			offset = (hints.Bounds.Dx() - width) / 2
+		case tomo.AlignEnd:
+			offset = hints.Bounds.Dx() - width
+		}
+		for _, box := range boxes {
+			box.SetBounds(box.Bounds().Add(image.Pt(offset, 0)))
+		}
+	}
+}
+
+func (contract Contract) v () bool { return contract == ContractVertical   }
+func (contract Contract) h () bool { return contract == ContractHorizontal }