Search the Community
Showing results for tags 'indexOf'.
Found 1 result
-
Hello,I want to make a script to check if there is anything drawn on a canvas.I tried to use this script: [/font][font=arial,helvetica,sans-serif]var ctx = document.getElementById("canvas").getContext("2d");[/font][font=arial,helvetica,sans-serif]/* Some other code, including some drawing code[/font][font=arial,helvetica,sans-serif]All drawings are black, with alpha value 255 */[/font] [font=arial,helvetica,sans-serif]var a = ctx.[color=#000000][size=1]getImageData(0,0,room.width,room.height)[/size][/color].data.indexOf(255); // to see if anything is drawn[/font][font=arial,helvetica,sans-serif] But for some reason it didn't work.I have also tested some other array methods, but they didn't work either on the imageData.dataIs there some way to make this work?Using a for loop instead would probably be to slow. Michiel
