Draw a texture rotated, BUT not around the center?

Garry's Mod coding
#1

Okay, so I’m recreating the CSS radar. Picture… It’s really simple, but right now it doesn’t rotate depending on your aim like in css. Does anyone know a way to draw a rotated texture on a defined axis and not the center? I’m guessing I could pull it off with Surface.DrawTexturedRectRotated, but I would have to set its position based on where I want to rotate it and how much it’s rotated. I bet that would be a pain in the ass… I figured I’d ask if anyone knows a way to do this before I attempt at it.

#2

[lua]
function DrawRotatedTexture( x, y, w, h, angle, cx, cy )

if( !cx and !cy ) then
	
	surface.DrawTexturedRectRotated( x, y, w, h, angle );
	
else
	
	local sin, cos = math.sin( math.rad( angle ) ), math.cos( math.rad( angle ) );
	
	x = x - sin * cx;
	y = y - cos * cy;
	
	surface.DrawTexturedRectRotated( x, y, w, h, angle );
	
end

end
[/lua]

I just woke up so I’m not sure if it will work, but you’ll probably get the idea.

#3

Makes sense. I’ll try it when I get home. :smiley: Thanks.

#4

Well it works to an extent… as long as cx and cy are equal. I get weird results when they aren’t.

It’s not working as expected though, like if I make cx and cy 0, it should rotate at the top left corner of the texture, not the center.

I’ll mess around with this though.

#5

I think it only works when its a square because sin/cos will just be an oval, its orientation might not be right to rotate with.

Might be able to use a vector and rotatearoundaxis? Maybe? lol

#6

Holy shit I love you. I would’ve never thought of that! It works perfectly.

[lua]function DrawRotatedTexture( x, y, w, h, angle, cx, cy )

if( !cx and !cy ) then
	
	surface.DrawTexturedRectRotated( x, y, w, h, angle )
	
else
	
	local vec = Vector( w/2-cx, cy-h/2, 0 )
	vec:Rotate( Angle(180, ( angle + 90 ) * -1, -180) )
	surface.DrawTexturedRectRotated( x+vec.x, y+vec.y, w, h, angle )
	
end

end[/lua]

#7

nitpicky, but allows you to specify only one of the c values.
[lua]function DrawRotatedTexture( x, y, w, h, angle, cx, cy )
cx,cy = cx or w/2,cy or w/2
if( cx == w/2 and cy == w/2 ) then

	surface.DrawTexturedRectRotated( x, y, w, h, angle )
	
else
	
	local vec = Vector( w/2-cx, cy-h/2, 0 )
	vec:Rotate( Angle(180, ( angle + 90 ) * -1, -180) )
	surface.DrawTexturedRectRotated( x+vec.x, y+vec.y, w, h, angle )
	
end

end[/lua]

#8

There was a problem with the angles… All fixed.

[lua]function DrawRotatedTexture( x, y, w, h, angle, cx, cy )
cx,cy = cx or w/2,cy or w/2
if( cx == w/2 and cy == w/2 ) then

	surface.DrawTexturedRectRotated( x, y, w, h, angle )
	
else
	
	local vec = Vector( w/2-cx, cy-h/2, 0 )
	vec:Rotate( Angle(180, angle, -180) )
	surface.DrawTexturedRectRotated( x-vec.x, y+vec.y, w, h, angle )
	
end

end[/lua]

Hehehe, now my radar is a lot better because of this. http://i30.tinypic.com/opdbgj.jpg

#9

CS:S Gamemode?