purpose: Set text properties for mglText
usage: mglTextSet(fontName,<fontSize>,<fontColor>,<fontVFlip>,<fontHFlip>,<fontRotation>,<fontBold>,<fontItalic>,<fontUnderline>,<fontStrikeThrough>)

mglOpen;
mglVisualAngleCoordinates(57,[16 12]);
mglTextSet('Helvetica',32,[0 0.5 1 1],0,0,0,0,0,0,0);
mglTextDraw('Hello There',[0 0]);
mglFlush;

purpose: Creates a texture from a string.
usage: tex = mglText('string')

mglOpen;
mglVisualAngleCoordinates(57,[16 12]);
mglTextSet('Helvetica',32,[0 0.5 1 1],0,0,0,0,0,0,0);
thisText = mglText('hello')
mglBltTexture(thisText,[0 0],'left','top');
mglFlush;

Normally you will only set one output argument which is a texture usable by mglBltTexture. But if you have two output arguments

[tex texMatrix] = mglText('hello');

texMatrix will contain a 2D matlab array that has a rendering of the text (i.e. it will have values from 0-255 that represent the string). You can modify this matrix as you want and then use mglCreateTexture to create it into a texture that can be displayed by mglBltTexture

purpose: wrapper around mglText and mglBltTexture to draw some text on the screen. If you need to draw text more quickly, you will have to pre-make the text textures with mglText and then use mglBltTexture when you want it. Otherwise, for non time-critical things this functions should be used.
usage: mglTextDraw(str,pos,<hAlignment>,<vAlignment>)

mglOpen;
mglVisualAngleCoordinates(57,[16 12]);
mglTextSet('Helvetica',32,[0 0.5 1 1],0,0,0,0,0,0,0);
mglTextDraw('Hello There',[0 0]);
mglFlush;

purpose: Draws a stroked fixed-width character or string on MGL display. Default width is 1, default height 1.8 (in current screen coordinates)
usage: [x,y]=mglStrokeText( string, x, y, scalex, scaley, linewidth, color, rotation );

mglOpen;
mglVisualAngleCoordinates(57,[16 12]);
mglStrokeText('Hello',0,0);
mglFlush;