package basicLayouts import "image" import "git.tebibyte.media/sashakoshka/tomo/layouts" import "git.tebibyte.media/sashakoshka/tomo/elements" // Horizontal arranges elements horizontally. Elements at the start of the entry // list will be positioned on the left, and elements at the end of the entry // list will positioned on the right. All elements have the same height. type Horizontal struct { // If Gap is true, a gap will be placed between each element. Gap bool // If Pad is true, there will be padding running along the inside of the // layout's border. Pad bool } // Arrange arranges a list of entries horizontally. func (layout Horizontal) Arrange ( entries []layouts.LayoutEntry, margin int, bounds image.Rectangle, ) { if layout.Pad { bounds = bounds.Inset(margin) } // get width of expanding elements expandingElementWidth := layout.expandingElementWidth ( entries, margin, bounds.Dx()) // set the size and position of each element dot := bounds.Min for index, entry := range entries { if index > 0 && layout.Gap { dot.X += margin } entry.Bounds.Min = dot entryWidth := 0 if entry.Expand { entryWidth = expandingElementWidth } else { entryWidth, _ = entry.MinimumSize() } dot.X += entryWidth entry.Bounds.Max = entry.Bounds.Min.Add(image.Pt(entryWidth, bounds.Dy())) entries[index] = entry } } // MinimumSize returns the minimum width and height that will be needed to // arrange the given list of entries. func (layout Horizontal) MinimumSize ( entries []layouts.LayoutEntry, margin int, ) ( width, height int, ) { for index, entry := range entries { entryWidth, entryHeight := entry.MinimumSize() if entryHeight > height { height = entryHeight } width += entryWidth if layout.Gap && index > 0 { width += margin } } if layout.Pad { width += margin * 2 height += margin * 2 } return } // FlexibleHeightFor Returns the minimum height the layout needs to lay out the // specified elements at the given width, taking into account flexible elements. func (layout Horizontal) FlexibleHeightFor ( entries []layouts.LayoutEntry, margin int, width int, ) ( height int, ) { if layout.Pad { width -= margin * 2 } // get width of expanding elements expandingElementWidth := layout.expandingElementWidth ( entries, margin, width) x, y := 0, 0 if layout.Pad { x += margin y += margin } // set the size and position of each element for index, entry := range entries { entryWidth, entryHeight := entry.MinimumSize() if entry.Expand { entryWidth = expandingElementWidth } if child, flexible := entry.Element.(elements.Flexible); flexible { entryHeight = child.FlexibleHeightFor(entryWidth) } if entryHeight > height { height = entryHeight } x += entryWidth if index > 0 && layout.Gap { x += margin } } if layout.Pad { height += margin * 2 } return } func (layout Horizontal) expandingElementWidth ( entries []layouts.LayoutEntry, margin int, freeSpace int, ) ( width int, ) { expandingElements := 0 // count the number of expanding elements and the amount of free space // for them to collectively occupy for index, entry := range entries { if entry.Expand { expandingElements ++ } else { entryMinWidth, _ := entry.MinimumSize() freeSpace -= entryMinWidth } if index > 0 && layout.Gap { freeSpace -= margin } } if expandingElements > 0 { width = freeSpace / expandingElements } return }