Bug: Selection is truncated if dragged to edge of summary graph

[timmc]

Reproduction:

• Go to Time Series demo
• Select e.g. the middle third of the summary view
• Drag it all the way to the left (or right), then back towards the center
• It is now much less than a third of the width of the summary graph

I can't tell if this is a Flotr or Envision bug. Appears in demos built from current master.

[timmc]

I spot-checked this demo through its history; this bug seems to have always been there.

[cesutherland]

Thanks. Sorry for the late response. This is an issue in the Flotr2 handles plugin. You'd expect that, once you reach the end of the graph, the selection stays 1/3 in size but stops moving with your mouse?

[Zielak]

I have found a solution. I'm github-newbie so instead of making pull request i'll just type my code here. I've made a change in envision.js file, line 5673, function mouseMoveHandler:

function mouseMoveHandler(e, position) {

  if (!this.handles.initialized) return;
  if (!this.handles.moveHandler) return;

  var
    delta = position.x - this.lastMousePos.x,
    selection = this.selection.selection,
    area = this.selection.getArea(),
    handles = this.handles;

  // added 2 if statements to check if selection can go any further.
  if(delta>0){
    if(selection.second.x + delta + 1 > this.canvasWidth) return false;
  }
  if(delta<0){
    if(selection.first.x + delta <= 0) return false;
  }

  handles.moveHandler(area, delta);
  checkSwap(area, handles);

  this.selection.setSelection(area);
}

Selection box never changes size when dragging over the edge.
Please let me know if this fix is satisfactory.

EDIT: Right now I see this fix isn't enough. When selection box reaches the edge it still gets smaller by pixels, but only for the first hit on drag.