Editing WoW:SetTexCoord Transformations (section)

===Simple rotation of square textures around the center===
While the above section about matrix manipulation gives a lot of flexibility, most often much simpler math suffice.
Here's an example of rotating a square texture around its center with an arbitrary angle:
 local s2 = sqrt(2);
 local cos, sin, rad = math.cos, math.sin, math.rad;
 local function CalculateCorner(angle)
 	local r = rad(angle);
 	return 0.5 + cos(r) / s2, 0.5 + sin(r) / s2;
 end
 local function RotateTexture(texture, angle)
 	local LRx, LRy = CalculateCorner(angle + 45);
 	local LLx, LLy = CalculateCorner(angle + 135);
 	local ULx, ULy = CalculateCorner(angle + 225);
 	local URx, URy = CalculateCorner(angle - 45);
 	
 	texture:SetTexCoord(ULx, ULy, LLx, LLy, URx, URy, LRx, LRy);
 end