png image problem, very newbie question

BlitzMax Forums/BlitzMax Beginners Area/png image problem, very newbie question

Pavlov

(Posted 2005) [#1]

I've got a png image with its background color set to RGB 0, 0, 0. When I try to use the image the images background keeps showing through, why? Below is my Draw method, any help would be greatly appreciated.

Thanks

' draw the city
Method Draw()
SetBlend MASKBLEND
SetAlpha 1
SetScale .4, .4
SetRotation 0
DrawImage city, x, y
End Method

xlsior

(Posted 2005) [#2]

Can't seem to find it now, but I seem to remember that 0,0,0 is the default mask color...

try setting a mask of 0,255,0 or some other color that you are unlikely to have used in your images?

tonyg

(Posted 2005) [#3]

There should be nothing wrong with what you have done in this part of the program. You have set a few options so it might be a case of not setting them back afterwards (or somewhere else in the program).
Try creating a simple program to see whether you have it working with this image...
e.g.

Graphics 800,600
back = LoadImage("background.png")
fore = LoadImage("fore.png")
While Not KeyHit(key_escape)
   Cls
      DrawImage back,0,0
      SetBlend MASKBLEND 
      SetAlpha 1 
      SetRotation 0 
      DrawImage fore,100,100
flip
Wend

ImaginaryHuman

(Posted 2005) [#4]

umm,.... MASKBLEND lets the background show through, that's what it's for. If you want to show the black pixels use SOLIDBLEND.

Pavlov

(Posted 2005) [#5]

I found out the problem, I had selected CMYK in photoshop. I changed it to RGB and it worked as it should. Thanks for everyones input.