ref: cb083ed612f90d648a7a5c27b8e155beef6c7bfb
dir: /browser/duitx/scroll.go/
package duitx
// Original code from github.com/mjl-/duit
//
// Copyright 2018 Mechiel Lukkien mechiel@ueber.net
//
// Permission is hereby granted, free of charge, to any person obtaining a copy of this
// software and associated documentation files (the "Software"), to deal in the Software
// without restriction, including without limitation the rights to use, copy, modify, merge,
// publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons
// to whom the Software is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all copies or
// substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
// INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
// PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
// HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
// SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
import (
"fmt"
"image"
"math"
"time"
"9fans.net/go/draw"
"github.com/mjl-/duit"
"github.com/psilva261/mycel/logger"
)
const maxAge = time.Minute
// Scroll shows a part of its single child, typically a box, and lets you scroll the content.
type Scroll struct {
Kid duit.Kid
Height int // < 0 means full height, 0 means as much as necessary, >0 means exactly that many lowdpi pixels
r image.Rectangle // entire ui
barR image.Rectangle
barActiveR image.Rectangle
childR image.Rectangle
Offset int // current scroll offset in pixels
img *draw.Image // for child to draw on
scrollbarSize int
lastMouseUI duit.UI
drawOffset int
tiles map[int]*draw.Image
last map[int]time.Time
tilesChanged bool
}
var _ duit.UI = &Scroll{}
// NewScroll returns a full-height scroll bar containing ui.
func NewScroll(dui *duit.DUI, ui duit.UI) *Scroll {
s := &Scroll{
Height: -1,
Kid: duit.Kid{UI: ui},
tiles: make(map[int]*draw.Image),
last: make(map[int]time.Time),
}
return s
}
func (ui *Scroll) Free() {
ui.tiles = make(map[int]*draw.Image)
ui.last = make(map[int]time.Time)
}
func (ui *Scroll) freeCur() {
i, of := ui.pos()
tl, ok := ui.tiles[i]
tl1, ok1 := ui.tiles[i+1]
if !ui.tilesChanged && (!ok || ui.sizeOk(tl)) && (of == 0 || !ok1 || ui.sizeOk(tl1)) {
return
}
if ui.tiles[i] != nil {
ui.tiles[i].Free()
delete(ui.tiles, i)
delete(ui.last, i)
}
if of > 0 {
if ui.tiles[i+1] != nil {
ui.tiles[i+1].Free()
delete(ui.tiles, i+1)
delete(ui.last, i+1)
}
}
ui.tilesChanged = false
}
func (ui *Scroll) sizeOk(tl *draw.Image) bool {
return tl != nil && tl.R.Dx() == ui.r.Dx() && tl.R.Dy() == ui.r.Dy()
}
func (ui *Scroll) ensure(dui *duit.DUI, i int) {
log.Printf("ensure(dui, %v)", i)
last, ok := ui.last[i]
tl, _ := ui.tiles[i]
if ok && time.Since(last) < maxAge && ui.sizeOk(tl) {
return
}
log.Printf("ensure(dui, %v): draw", i)
r := ui.r.Add(image.Point{X: 0, Y: i * ui.r.Dy()})
img, err := dui.Display.AllocImage(r, draw.ARGB32, false, dui.BackgroundColor)
if duitError(dui, err, "allocimage") {
return
}
ui.Kid.UI.Draw(dui, &ui.Kid, img, image.ZP, draw.Mouse{}, true)
if ui.tiles[i] != nil {
ui.tiles[i].Free()
ui.tiles[i] = nil
}
log.Printf("ensure: ui.tiles[%d] = img(R=%+v, ...)", i, img.R)
ui.tiles[i] = img
ui.last[i] = time.Now()
for j, t := range ui.tiles {
if math.Abs(float64(i-j)) > 5 {
t.Free()
delete(ui.tiles, j)
delete(ui.last, j)
}
}
}
func (ui *Scroll) pos() (t, of int) {
t = ui.Offset / ui.r.Dy()
of = ui.Offset % ui.r.Dy()
return
}
func (ui *Scroll) tlR(i int) (r image.Rectangle) {
r.Min.X = ui.r.Min.X
r.Max.X = ui.r.Max.X
r.Min.Y = ui.r.Min.Y + i*ui.r.Dy()
r.Max.Y = r.Min.Y + ui.r.Dy()
return
}
func (ui *Scroll) Layout(dui *duit.DUI, self *duit.Kid, sizeAvail image.Point, force bool) {
debugLayout(dui, self)
if self.Layout == duit.Clean && !force {
return
}
self.Layout = duit.Clean
self.Draw = duit.Dirty
// todo: be smarter about DirtyKid
ui.scrollbarSize = dui.Scale(duit.ScrollbarSize)
scaledHeight := dui.Scale(ui.Height)
if scaledHeight > 0 && scaledHeight < sizeAvail.Y {
sizeAvail.Y = scaledHeight
}
ui.r = rect(sizeAvail)
ui.barR = ui.r
ui.barR.Max.X = ui.barR.Min.X + ui.scrollbarSize
ui.childR = ui.r
ui.childR.Min.X = ui.barR.Max.X
// todo: only force when sizeAvail or childR changed?
ui.Kid.UI.Layout(dui, &ui.Kid, image.Pt(ui.r.Dx()-ui.barR.Dx(), ui.r.Dy()), force)
ui.Kid.Layout = duit.Clean
ui.Kid.Draw = duit.Dirty
kY := ui.Kid.R.Dy()
if ui.r.Dy() > kY && ui.Height == 0 {
ui.barR.Max.Y = kY
ui.r.Max.Y = kY
ui.childR.Max.Y = kY
}
self.R = rect(ui.r.Size())
ui.Free()
}
func (ui *Scroll) Draw(dui *duit.DUI, self *duit.Kid, img *draw.Image, orig image.Point, m draw.Mouse, force bool) {
debugDraw(dui, self)
if self.Draw == duit.Clean {
return
} else {
log.Printf("Draw: self.Draw=%v is not clean, force=%v", self.Draw, force)
}
if ui.r.Empty() {
self.Draw = duit.Clean
return
}
ui.drawBar(dui, self, img, orig, m, force)
ui.drawChild(dui, self, img, orig, m, force)
self.Draw = duit.Clean
}
func (ui *Scroll) drawBar(dui *duit.DUI, self *duit.Kid, img *draw.Image, orig image.Point, m draw.Mouse, force bool) {
// ui.scroll(0)
barHover := m.In(ui.barR)
bg := dui.ScrollBGNormal
vis := dui.ScrollVisibleNormal
if barHover {
bg = dui.ScrollBGHover
vis = dui.ScrollVisibleHover
}
h := ui.r.Dy()
uih := ui.Kid.R.Dy()
if uih > h {
barR := ui.barR.Add(orig)
img.Draw(barR, bg, nil, image.ZP)
barH := h * h / uih
barY := ui.Offset * h / uih
ui.barActiveR = ui.barR
ui.barActiveR.Min.Y += barY
ui.barActiveR.Max.Y = ui.barActiveR.Min.Y + barH
barActiveR := ui.barActiveR.Add(orig)
barActiveR.Max.X -= 1 // unscaled
img.Draw(barActiveR, vis, nil, image.ZP)
}
}
func (ui *Scroll) drawChild(dui *duit.DUI, self *duit.Kid, img *draw.Image, orig image.Point, m draw.Mouse, force bool) {
// draw child ui
if ui.childR.Empty() {
return
}
var i, of int
var tl, tl1 *draw.Image
var ok, ok1, ok2, ok3, okm1, okm2 bool
p := draw.Point{X: 0, Y: ui.Offset}
n := draw.Point{X: 0, Y: -ui.Offset}
predrawCur := func() {
// tile draw
i, of = ui.pos()
tl, ok = ui.tiles[i]
tl1, ok1 = ui.tiles[i+1]
if !ok {
ui.ensure(dui, i)
}
if !ok1 {
ui.ensure(dui, i+1)
}
if !ok {
tl, _ = ui.tiles[i]
}
if !ok1 && of > 0 {
tl1, _ = ui.tiles[i+1]
}
}
predrawFut := func() {
// tile draw
i, of = ui.pos()
tl1, ok1 = ui.tiles[i+1]
_, ok2 = ui.tiles[i+2]
_, ok3 = ui.tiles[i+3]
if i > 0 {
_, okm1 = ui.tiles[i-1]
}
if i > 1 {
_, okm2 = ui.tiles[i-2]
}
if of == 0 && !ok1 {
ui.ensure(dui, i+1)
}
if ok1 && !ok2 {
ui.ensure(dui, i+2)
}
if ok2 && !ok3 {
ui.ensure(dui, i+3)
}
if i > 0 && !okm1 {
ui.ensure(dui, i-1)
}
if i > 1 && okm1 && !okm2 {
ui.ensure(dui, i-2)
}
}
defer predrawFut()
if self.Draw == duit.DirtyKid {
ui.freeCur()
ui.Kid.Draw = duit.Clean
} else if ui.Kid.Draw != duit.Clean || force {
log.Printf("drawChild: refresh: ui.Kid.Draw=%v force=%v", ui.Kid.Draw, force)
ui.freeCur()
tmp := img.Clipr
img.ReplClipr(false, ui.childR.Add(orig))
ui.Kid.UI.Draw(dui, &ui.Kid, img, orig.Add(ui.childR.Min).Add(n), draw.Mouse{}, true)
img.ReplClipr(false, tmp)
ui.Kid.Draw = duit.Clean
return
}
predrawCur()
rTop := draw.Rectangle{
Min: ui.childR.Min,
Max: draw.Point{
X: ui.childR.Max.X,
Y: ui.childR.Max.Y - of,
},
}
rBtm := draw.Rectangle{
Min: draw.Point{
X: ui.childR.Min.X,
Y: rTop.Max.Y,
},
Max: ui.childR.Max,
}
pOf := draw.Point{X: 0, Y: ui.Offset + rTop.Dy()}
img.Draw(rTop.Add(orig), tl, nil, p)
if of > 0 {
img.Draw(rBtm.Add(orig), tl1, nil, pOf)
}
return
}
func (ui *Scroll) scroll(delta int) (changed bool) {
o := ui.Offset
ui.Offset += delta
ui.Offset = maximum(0, ui.Offset)
ui.Offset = minimum(ui.Offset, maximum(0, ui.Kid.R.Dy()-ui.childR.Dy()))
return o != ui.Offset
}
func (ui *Scroll) scrollKey(k rune) (consumed bool) {
switch k {
case draw.KeyUp:
return ui.scroll(-50)
case draw.KeyDown:
return ui.scroll(50)
case draw.KeyPageUp:
return ui.scroll(-200)
case draw.KeyPageDown:
return ui.scroll(200)
}
return false
}
func (ui *Scroll) scrollMouse(m draw.Mouse, scrollOnly bool) (consumed bool) {
switch m.Buttons {
case duit.Button4:
return ui.scroll(-m.Y / 4)
case duit.Button5:
return ui.scroll(m.Y / 4)
}
if scrollOnly {
return false
}
switch m.Buttons {
case duit.Button1:
return ui.scroll(-m.Y)
case duit.Button2:
Offset := m.Y * ui.Kid.R.Dy() / ui.barR.Dy()
OffsetMax := ui.Kid.R.Dy() - ui.childR.Dy()
Offset = maximum(0, minimum(Offset, OffsetMax))
o := ui.Offset
ui.Offset = Offset
return o != ui.Offset
case duit.Button3:
return ui.scroll(m.Y)
}
return false
}
func (ui *Scroll) result(dui *duit.DUI, self *duit.Kid, r *duit.Result, scrolled bool) {
if ui.Kid.Layout != duit.Clean {
ui.Kid.UI.Layout(dui, &ui.Kid, ui.childR.Size(), false)
ui.Kid.Layout = duit.Clean
ui.Kid.Draw = duit.Dirty
self.Draw = duit.Dirty
if r.Consumed && !scrolled {
ui.tilesChanged = true
}
} else if ui.Kid.Draw != duit.Clean || scrolled {
self.Draw = duit.Dirty
if r.Consumed && !scrolled {
ui.tilesChanged = true
}
}
}
func (ui *Scroll) Mouse(dui *duit.DUI, self *duit.Kid, m draw.Mouse, origM draw.Mouse, orig image.Point) (r duit.Result) {
nOrigM := origM
nOrigM.Point = nOrigM.Point.Add(image.Pt(-ui.scrollbarSize, ui.Offset))
nm := m
nm.Point = nm.Point.Add(image.Pt(-ui.scrollbarSize, ui.Offset))
if m.Buttons == 0 {
ui.Kid.UI.Mouse(dui, &ui.Kid, nm, nOrigM, image.ZP) // comment this to have no flicker after mouse move and then scroll
return
}
if m.Point.In(ui.barR) {
r.Hit = ui
r.Consumed = ui.scrollMouse(m, false)
self.Draw = duit.Dirty
return
} else if m.Point.In(ui.childR) {
r.Consumed = ui.scrollMouse(m, true)
if r.Consumed {
self.Draw = duit.Dirty
return
}
r = ui.Kid.UI.Mouse(dui, &ui.Kid, nm, nOrigM, image.ZP)
if r.Consumed {
self.Draw = duit.Dirty
ui.tilesChanged = true
log.Printf("Mouse: set ui.tilesChanged = true")
}
}
return
}
func (ui *Scroll) Key(dui *duit.DUI, self *duit.Kid, k rune, m draw.Mouse, orig image.Point) (r duit.Result) {
if m.Point.In(ui.barR) {
r.Hit = ui
r.Consumed = ui.scrollKey(k)
if r.Consumed {
self.Draw = duit.Dirty
}
}
if m.Point.In(ui.childR) {
log.Printf("Key: in ui.childR (self.Draw=%v)", self.Draw)
m.Point = m.Point.Add(image.Pt(-ui.scrollbarSize, ui.Offset))
scrolled := ui.scrollKey(k)
if scrolled {
self.Draw = duit.Dirty
r.Consumed = scrolled
return
}
r = ui.Kid.UI.Key(dui, &ui.Kid, k, m, image.ZP)
ui.warpScroll(dui, self, r.Warp, orig)
ui.result(dui, self, &r, scrolled)
log.Printf("Key: in ui.childR (self.Draw'=%v)", self.Draw)
}
return
}
func (ui *Scroll) warpScroll(dui *duit.DUI, self *duit.Kid, warp *image.Point, orig image.Point) {
if warp == nil {
return
}
Offset := ui.Offset
if warp.Y < ui.Offset {
ui.Offset = maximum(0, warp.Y-dui.Scale(40))
} else if warp.Y > ui.Offset+ui.r.Dy() {
ui.Offset = minimum(ui.Kid.R.Dy()-ui.r.Dy(), warp.Y+dui.Scale(40)-ui.r.Dy())
}
if Offset != ui.Offset {
if self != nil {
self.Draw = duit.Dirty
} else {
dui.MarkDraw(ui)
}
}
warp.Y -= ui.Offset
warp.X += orig.X + ui.scrollbarSize
warp.Y += orig.Y
}
func (ui *Scroll) _focus(dui *duit.DUI, p *image.Point) *image.Point {
if p == nil {
return nil
}
pp := p.Add(ui.childR.Min)
p = &pp
ui.warpScroll(dui, nil, p, image.ZP)
return p
}
func (ui *Scroll) FirstFocus(dui *duit.DUI, self *duit.Kid) *image.Point {
p := ui.Kid.UI.FirstFocus(dui, &ui.Kid)
return ui._focus(dui, p)
}
func (ui *Scroll) Focus(dui *duit.DUI, self *duit.Kid, o duit.UI) *image.Point {
if o == ui {
p := image.Pt(minimum(ui.scrollbarSize/2, ui.r.Dx()), minimum(ui.scrollbarSize/2, ui.r.Dy()))
return &p
}
p := ui.Kid.UI.Focus(dui, &ui.Kid, o)
return ui._focus(dui, p)
}
func (ui *Scroll) Mark(self *duit.Kid, o duit.UI, forLayout bool) (marked bool) {
if self.Mark(o, forLayout) {
return true
}
marked = ui.Kid.UI.Mark(&ui.Kid, o, forLayout)
if marked {
if forLayout {
if self.Layout == duit.Clean {
self.Layout = duit.DirtyKid
}
} else {
if self.Layout == duit.Clean {
self.Draw = duit.DirtyKid
}
}
}
return
}
func (ui *Scroll) Print(self *duit.Kid, indent int) {
what := fmt.Sprintf("Scroll Offset=%d childR=%v", ui.Offset, ui.childR)
duit.PrintUI(what, self, indent)
ui.Kid.UI.Print(&ui.Kid, indent+1)
}
//////////////////////
// //
// helper functions //
// //
//////////////////////
func pt(v int) image.Point {
return image.Point{v, v}
}
func rect(p image.Point) image.Rectangle {
return image.Rectangle{image.ZP, p}
}
func extendY(r image.Rectangle, dy int) image.Rectangle {
r.Max.Y += dy
return r
}
func insetPt(r image.Rectangle, pad image.Point) image.Rectangle {
r.Min = r.Min.Add(pad)
r.Max = r.Max.Sub(pad)
return r
}
func outsetPt(r image.Rectangle, pad image.Point) image.Rectangle {
r.Min = r.Min.Sub(pad)
r.Max = r.Max.Add(pad)
return r
}
func minimum64(a, b int64) int64 {
if a < b {
return a
}
return b
}
func maximum64(a, b int64) int64 {
if a > b {
return a
}
return b
}
func minimum(a, b int) int {
if a < b {
return a
}
return b
}
func maximum(a, b int) int {
if a > b {
return a
}
return b
}
func debugLayout(d *duit.DUI, self *duit.Kid) {
if d.DebugLayout > 0 {
log.Printf("duit: Layout %T %s layout=%d draw=%d\n", self.UI, self.R, self.Layout, self.Draw)
}
}
func debugDraw(d *duit.DUI, self *duit.Kid) {
if d.DebugDraw > 0 {
log.Printf("duit: Draw %T %s layout=%d draw=%d\n", self.UI, self.R, self.Layout, self.Draw)
}
}
func duitError(d *duit.DUI, err error, msg string) bool {
if err == nil {
return false
}
go func() {
d.Error <- fmt.Errorf("%s: %s", msg, err)
}()
return true
}