IDE: Optimization of modification events processing in text editors.
Too many modifications types where registered, and then too many events were fired.
Also, in case of uninterrupted sequence of events, updates to the model is deferred to the end of that sequence (wx.Callafter).
// widget_scrollbar.ysl2
widget_desc("ScrollBar") {
longdesc
||
ScrollBar - svg:rect based scrollbar
||
shortdesc > ScrollBar
path name="value" accepts="HMI_INT" > value
path name="range" accepts="HMI_INT" > range
path name="visible" accepts="HMI_INT" > visible
}
widget_class("ScrollBar") {
||
frequency = 10;
position = undefined;
range = undefined;
size = undefined;
mincursize = 0.1;
dispatch(value,oldval, index) {
switch(index) {
case 0:
this.range = Math.max(1,value);
break;
case 1:
this.position = value;
break;
case 2:
this.size = value;
break;
}
this.request_animate();
}
get_ratios() {
let range = this.range;
let size = Math.max(range * this.mincursize, Math.min(this.size, range));
let maxh = this.range_elt.height.baseVal.value;
let pixels = maxh;
return [size, maxh, range, pixels];
}
animate(){
if(this.position == undefined || this.range == undefined || this.size == undefined)
return;
let [size, maxh, range, pixels] = this.get_ratios();
let new_y = this.range_elt.y.baseVal.value + Math.round(Math.min(this.position,range-size) * pixels / range);
let new_height = Math.round(maxh * size/range);
this.cursor_elt.y.baseVal.value = new_y;
this.cursor_elt.height.baseVal.value = new_height;
}
init_mandatory() {
this.cursor_elt.onpointerdown = () => this.on_cursor_down();
this.bound_drag = this.drag.bind(this);
this.bound_drop = this.drop.bind(this);
}
apply_position(position){
this.position = Math.round(Math.max(Math.min(position, this.range - this.size), 0));
this.apply_hmi_value(1, this.position);
}
on_page_click(is_up){
this.apply_position(is_up ? this.position-this.size
: this.position+this.size);
}
on_cursor_down(e){
// get scrollbar -> root transform
let ctm = this.range_elt.getCTM();
// relative motion -> discard translation
ctm.e = 0;
ctm.f = 0;
// root -> scrollbar transform
this.invctm = ctm.inverse();
svg_root.addEventListener("pointerup", this.bound_drop, true);
svg_root.addEventListener("pointermove", this.bound_drag, true);
this.dragpos = this.position;
}
drop(e) {
svg_root.removeEventListener("pointerup", this.bound_drop, true);
svg_root.removeEventListener("pointermove", this.bound_drag, true);
}
drag(e) {
let [size, maxh, range, pixels] = this.get_ratios();
if(pixels == 0) return;
let point = new DOMPoint(e.movementX, e.movementY);
let movement = point.matrixTransform(this.invctm).y;
this.dragpos += movement * range / pixels;
this.apply_position(this.dragpos);
}
||
}
widget_defs("ScrollBar") {
labels("cursor range");
const "pagebuttons" optional_labels("pageup pagedown");
const "have_pagebuttons","string-length($pagebuttons)>0";
value "$pagebuttons";
| init: function() {
| this.init_mandatory();
if "$have_pagebuttons" {
| this.pageup_elt.onclick = () => this.on_page_click(true);
| this.pagedown_elt.onclick = () => this.on_page_click(false);
}
| },
}