WritePixels, empty image.

Monkey Targets Forums/Flash/WritePixels, empty image.

Polan

(Posted 2012) [#1]

I'm trying new WritePixel method but I can't write pixels to image.
I get empty image on debug and release, also if I change fog.WritePixels(fogtab , 0,0,sx,sy , 0,0)
to fog.WritePixels(fogtab , 4,4,sx,sy , 0,0) I get 4 pixel white border, and no "out of array" error.
Any ideas?

		fog = CreateImage(sx,sy)
		Local fogtab%[sx*sy]
		For Local x% = 0 To sx-1
			For Local y% = 0 To sy-1
				fogtab[x*sy+y] = ToARGB(256,256,256,256) ' returns 65536 so it's binary 111....., should be full white.
			Next
		Next
		fog.WritePixels(fogtab , 0,0,sx,sy , 0,0)
			End Method
	Method ToARGB%(r%,g%,b%,a%)
		Local argb%
		argb = a Shl 8
		argb = r Shl 8
		argb = g Shl 8
		argb = b Shl 8
		Return argb
			End Method

Polan

(Posted 2012) [#2]

Nvm, I found the bug.

PixelPiledriver

(Posted 2012) [#3]

So what was the bug?

Rone	(Posted 2012) [#4]

obviously 'ToARGB(256,256,256,256)', while the maximum is 255 per channel and
also 'ToARGB' itself, cause it uses only the green channel..

My_Fat_Fox

(Posted 2014) [#5]

I know this is an old thread, but for anyone struggling with this, as I was, here's a corrected version that works:

local color_red:Int = 255
local color_green:Int = 0
local color_blue:Int = 0
local alpha:Int = 255

fog = CreateImage(image_width, image_height)
Local fogtab%[image_width * image_height]
For Local x% = 0 To image_width-1
For Local y% = 0 To image_height-1
fogtab[x * image_height + y] = ToARGB(alpha, color_red, color_green, color_blue) 'This will be red
Next
Next
fog.WritePixels(fogtab , 0, 0,image_width,image_height , 0,0)

'This works to generate the right colors
Method ToARGB%(r%,g%,b%,a%)
Local argb%
argb = a | b Shl 8 | g Shl 16 | r Shl 24
Return argb
End Method

Obviously you also need to render the image in OnRender for example:

DrawImage(fog, 0, 0)