drawTopLeft
Draws text where the top left of the first glyph is at x, y
This is the low level draw method (all other draw methods end up calling this). It is unusual for application code to call this directly, because you normally want to specify a HAlignment and TextVAlignment, and have the x calculated for you!
Return
true iff all glyphs were found
Parameters
How many columns does a tab character advance by.
Often not required. Imaging we want to draw the text : H TAB ello (without the spaces), with 4 columns per indentation. The TAB character will only advance by 3 columns (because of the 'H'). Now suppose we want to color the 'H' red, and the rest blue. That's two separate calls. The second call must set startColumn to 1, so that we know that the TAB should only advance by 3 columns. We don't need to know the actual column number, only modulo indentationColumns. e.g. in this example, 1 and 5 would both be fine.