externalize drawing script

[confetti] / static / therapy_draw.js

diff --git a/static/therapy_draw.js b/static/therapy_draw.js
new file mode 100755 (executable)
index 0000000..0b5dffa
--- /dev/null
+++ b/static/therapy_draw.js
@@ -0,0 +1,112 @@
+// Copyright 2016 Paul Hänsch
+//
+// This file is part of Confetti.
+// 
+// Confetti is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+// 
+// Confetti is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+// 
+// You should have received a copy of the GNU Affero General Public License
+// along with Confetti.  If not, see <http://www.gnu.org/licenses/>. 
+
+body = document.body
+dbg = document.getElementById("jsdebug")
+canvas = document.getElementById("canvas")
+data=document.getElementById("image_serialize")
+
+image = canvas.getContext("2d")
+mouse = 0
+image_serialize=""
+
+// start and current coordinates of a draw
+// serves for tracking, whether path ends close to its beginning
+stx=0, sty=0
+cux=0, cuy=0
+
+function setcol(c) {
+  this.c = c
+  image.strokeStyle = c
+  image.fillStyle =  c
+  if ( c == "#FFF" ) image.lineWidth = 32
+  else image.lineWidth = 4
+  data.value += " stroke " + c + " stroke-width " + image.lineWidth
+}
+
+setcol("$tpy[color]")
+
+function relX(x){
+  if ( body.clientWidth >= 800 ){
+    return Math.floor(cscaleW * (x - canvas.offsetLeft))
+  } else { 
+    return Math.floor(cscaleW * (x - canvas.offsetLeft + window.pageXOffset))
+  }
+}
+function relY(y){
+  if ( body.clientWidth >= 800 ){
+    return Math.floor(cscaleH * (y - canvas.offsetTop))
+  } else { 
+    return Math.floor(cscaleH * (y - canvas.offsetTop + window.pageYOffset))
+  }
+}
+
+function draw(x, y) {
+  if ( mouse == 1){
+    cux=relX(x), cuy=relY(y)
+
+    image.lineTo( cux, cuy )
+    image.stroke()
+
+    image_serialize += " " + cux + "," + cuy
+  }
+}
+
+function drawstart(x, y) {
+  mouse = 1
+
+  cscaleW = canvas.width / canvas.clientWidth
+  cscaleH = canvas.height / canvas.clientHeight
+
+  stx=relX(x), sty=relY(y)
+
+  image.beginPath()
+  draw(x, y)  // why must this not use relative Coords ???
+
+  image_serialize = " polyline"
+}
+
+function drawstop() {
+ 
+  // if path ends close to beginning ( < 50 px); then close path and fill
+  if ( mouse == 1 && Math.sqrt( Math.pow(stx - cux, 2) + Math.pow(sty - cuy, 2)) <= 50 && c !== "#FFF" ){
+    image.lineTo( stx, sty )
+    image.stroke()
+
+    image.globalAlpha = .5
+    image.fill()
+    image.globalAlpha = 1
+
+    image_serialize += " " + stx + "," + sty
+    data.value += " fill " + c + "8" + image_serialize
+  } else if (mouse == 1)  {
+    data.value += " fill #0000 " + image_serialize
+  }
+  dbg.innerHTML = " stx: " + stx + " cux: " + cux + " sty: " + sty + " cuy: " + cuy
+ 
+  image.closePath()
+  image_serialize = ""
+  mouse = 0
+}
+
+window.addEventListener( 'mouseup',   function()   { drawstop() } )
+canvas.addEventListener( 'mousedown', function(e)  { drawstart(e.clientX, e.clientY) } )
+canvas.addEventListener( 'mousemove', function(e)  {      draw(e.clientX, e.clientY) } )
+
+window.addEventListener( 'touchend',   function()  { drawstop() } )
+canvas.addEventListener( 'touchstart', function(e) { drawstart(e.touches[0].clientX, e.touches[0].clientY) } )
+canvas.addEventListener( 'touchmove',  function(e) { e.preventDefault(); draw(e.touches[0].clientX, e.touches[0].clientY) } )