Need help in gpu.copy()

[Gladox114 1]

The gpu.copy() is a little bit bugged i would say or i use it wrong

 

 

local c = require("component")
local gpu2 = c.proxy(c.get("009"))
gpu2.setBackground(0xCC0000) -- setting background to red
local x,y = gpu2.getResolution()
gpu2.fill(1,1,x,y," ")       -- fill the whole screen red
gpu2.setBackground(0x000000) -- setting background to black
gpu2.fill(1,1,x,y/2," ")     -- fill the top half screen black
os.sleep(2)
gpu2.copy(1,y/2,x,y/2,1,1)   -- copy the red half bottom to the half top
print(y/2) -- just to check if i calculate something wrong
os.sleep(2)

 

And it doesn't work at all as you can see in the picture...

I maybe need some examples and tutorials for this.

[CptMercury 6]

The inputs for gpu.copy() are x, y, width, height, x_offset (relative position to x; so the new rectangle starts at coordinate x - tx), y_offset (same as for x_offset).

So basically if you want to copy the lower part to the upper part, you have to call: 

gpu.copy(1, y/2, x, y, 0, -y/2)
-- x_offset is 0 because you want to have the rectangle at the same x position as the old one
-- y_offset is -y/2 (-25 for tier 3 screen), because the rectangle starts at a smaller y value compared to the old one

 

[Gladox114 1]

Thx for explaining it because i didn't understood the meaning of tx and ty in the gpu API ^^