javascript - iPad HTML5 canvas not refreshing -

-

edit: demo code found in "parallelogram explorer" tab here: http://atmdev01.procloud.net/geometry_tools9/

so i'm calling following javascript function @ document load draw perimeter of parallelogram, , working fine that. issue when call function touchmove handler allow ipad user adjust size of parallelogram, canvas not redrawing shape. in fact not responding @ all. i've run alerts verify function being run , is.

could issue way i'm clearing canvas (the "canvas.width = canvas.width + 0" method) or refresh rates on ipad?

the interesting part it's working in desktop browser using mousemove, not on ipad using touchmove. please advise...

(the "corners" in code areas user can touch , drag resize parallelogram)

this.drawsides = function() {     var order = [1, 2, 4, 3];     var canvas = document.getelementbyid("canvas");     var ctx = canvas.getcontext("2d");     var firstcorner = this.getcornerobj(1);     var secondcorner = this.getcornerobj(2);         var firstcorneropp = this.getcornerobj(firstcorner.opp);     var secondcorneropp = this.getcornerobj(secondcorner.opp);            /* clear canvas , draw parallelogram provided corners */     canvas.width = canvas.width + 0; //clears canvas faster clearrect     ctx.beginpath();     (i in order) {         if (i < order.length) {             var cornerobj = this.getcornerobj(order[i]);             if (order[i] > 1) {                 var prevobj = this.getcornerobj(order[i-1]);                 ctx.moveto(prevobj.x  + (prevobj.width)/2, prevobj.y + (prevobj.height)/2);                 ctx.lineto(cornerobj.x + (cornerobj.width)/2, cornerobj.y + (cornerobj.height)/2);                               }         }     }      ctx.lineto(firstcorner.x + (firstcorner.width)/2, firstcorner.y + (firstcorner.height)/2);     ctx.strokestyle = "#300";     ctx.stroke(); }

the canvas isn't cleared canvas.width = canvas.width; in safari.


Comments

Post a Comment

Popular posts from this blog

Javascript line number mapping -

-
magically formatted comments change reported line number of javascript errors in browsers; this: //@line n "f" n line number , f file name. unfortunately, //@line appears ungoogleable. know there documentation on feature, , browsers support it? (i found references here , here .) from can find available in mozilla based browsers. it using js_setoptions command can turn these options on or off depending on values passed. https://developer.mozilla.org/en/js_setoptions
Read more

c# - Is it possible to remove an existing registration from Autofac container builder? -

-
something along lines: builder.registertype<mytype>().as<itype>(); builder.registertype<mytype2>().as<itype>(); builder.deregistertype<mytype>().as<itype>() var container = builder.build(); var types = container.resolve<ienumerable<itype>>(); assert.istrue(types.count == 1); assert.istrue(types[0].gettype == typeof(mytype2)); scenario: go through bunch of assemblies , go register types want make sure have 1 implementation of given type. need before create container. track on own nice if autofac me bit. this cannot done directly using containerbuilder , unless start on new one. mind you, having first built container should able construct new container filtering away unwanted types , reusing registrations first container. this: ... var container = builder.build(); builder = new containerbuilder(); var components = container.componentregistry.registrations .where(cr => cr.activator.limittype != typ...
Read more

php - Mysql PK and FK char(36) vs int(10) -

-
i have read mysql can handle indexes , searches better if tables keys integers rather char(36) uuid's. is worth converting int(10)? note: use 1 server , have have plans use multiple databases concurrently therefore removing 1 of big reasons using uuid. our tables innodb if makes difference. thanks in advance. usually rdbms can handle integer keys pk more efficient, other datatypes. reason how build index column, yes: long dont require string (or other typed) keys, should use integers. however: char(36) , int(10) far away being equal, because int(10) much smaller, char(36). dont know, if require many different keys, should keep in mind. update, complete last paragraph: int(10) 32-bit, char(36) 36 - ^byte^ (= 288-bit). not mean, int consumes less space, means, char(36) has 4 times more different keys.
Read more