Added an Icon element

elements/basic/icon.go

@@ -0,0 +1,70 @@
+package basicElements
+
+import "image"
+import "git.tebibyte.media/sashakoshka/tomo/theme"
+import "git.tebibyte.media/sashakoshka/tomo/artist"
+import "git.tebibyte.media/sashakoshka/tomo/elements/core"
+
+type Icon struct {
+	*core.Core
+	core  core.CoreControl
+	theme theme.Wrapped
+	id    theme.Icon
+	size  theme.IconSize
+}
+
+func NewIcon (id theme.Icon, size theme.IconSize) (element *Icon) {
+	element = &Icon {
+		id:   id,
+		size: size,
+	}
+	element.theme.Case = theme.C("basic", "icon")
+	element.Core, element.core = core.NewCore(element.draw)
+	element.updateMinimumSize()
+	return
+}
+
+// SetTheme sets the element's theme.
+func (element *Icon) SetTheme (new theme.Theme) {
+	if new == element.theme.Theme { return }
+	element.theme.Theme = new
+	element.updateMinimumSize()
+	if element.core.HasImage() {
+		element.draw()
+		element.core.DamageAll()
+	}
+}
+
+func (element *Icon) icon () artist.Icon {
+	return element.theme.Icon(element.id, element.size)
+}
+
+func (element *Icon) updateMinimumSize () {
+	icon := element.icon()
+	if icon == nil {
+		element.core.SetMinimumSize(0, 0)
+	} else {
+		bounds := icon.Bounds()
+		element.core.SetMinimumSize(bounds.Dx(), bounds.Dy())
+	}
+}
+
+func (element *Icon) draw () {
+	bounds := element.Bounds()
+	state  := theme.State { }
+	element.theme.
+		Pattern(theme.PatternBackground, state).
+		Draw(element.core, bounds)
+	icon := element.icon()
+	if icon != nil {
+		iconBounds := icon.Bounds()
+		offset := image.Pt (
+			(bounds.Dx() - iconBounds.Dx()) / 2,
+			(bounds.Dy() - iconBounds.Dy()) / 2)
+		icon.Draw (
+			element.core,
+			element.theme.Color (
+				theme.ColorForeground, state),
+			bounds.Min.Add(offset))
+	}
+}