Progress update.

Author: pjbaron

docs/_phaser_tilemap_GL_progress.txt

@@ -77,4 +77,7 @@ Ran a profiler on my code using FireFox which runs the sci-fly demo extremely sl
 
 The batch changes are in, in a very rough form.  The entire visible screen is now drawn with a single gl.drawArrays call after the JS sets up a large VBO with degenerate tris to separate the individual tiles from each other.  This approach was hugely successful at drawing in the "pbRenderer" (now called "Beam"), however it is still choking FireFox.  Further investigation is needed including: test the old pbRenderer demos to make sure they don't choke FireFox, if it does then check the PIXI 4 tilemap renderer to see if that does too.  If the old demos work properly, then compare them with this new implementation line-by-line to find out what's causing the problem now.
 
+False alarm? After a restart FireFox is now running the new demo correctly (60 fps)... I'm certain I cleared the cache before testing the new version, but maybe there was something jamming up the GPU which got cleared when I reset the browser.  Still, this is good news, and now I can go ahead and finish this implementation with proper scroll offsets then get Rich to test it on his rig.
+Added the scroll offsets and gave the code a cursory first-pass clean up.  I've noticed that when switching from Chrome to FireFox it runs slowly for a few seconds before settling in to the solid 60 fps... I think this might be some webgl feature not being cleaned up immediately after Chrome closes because it's very consistent.
 
+Next coding task is to modify the Tileset class to remove the 'draw' function, and use it's firstgid value so that more of the Phaser tileset examples will work correctly.