Skewed Image Map.. why?

[Feyszar]

Hi guys,
I played around with the image map shader and read a lot about it in the forums. I thought I learned enough about it to start my first try... somehow I missed something, I guess.

I positioned a cam(topoCam) straight above the terrain (-90°), rendered (800x600) and modified it with photoshop to mask certain areas (black/white). The attached image shows the mask of the shoreline.
I plugged the image map shader into a surface layer, set the projection type to "through camera" and assigned the topoCam as projection camera. Somehow the result was not what I expected. I played around with the size and projection type without success  Unfortunately I don't know which size my terrain-file has, because it's a really old one from my TG0.9.

Any idea guys?

[cyphyr]

Try using an ortho Camera instead, that way you wont get any distortions and use plan y projection (set the size and dimensions to match your Ortho cams data and it will match perfectly).
Good luck
Richard

[Feyszar]

Thank cyphyr,
I remember (faintly) about the ortho-cam thing. Just tried it but still have problems matching size and dimensions. Could you go further into detail? Which size and dimensions? From the mask (800x600)?
I set the ortho-cam to "use ortho height" to 4500.

[cyphyr]

If you place the ortho camera above the centre of your island and input the ortho width to something that will encompass the island (ie slightly bigger) note down the position of your camera (just the x and z). These two numbers will be the centre of your imagemap shader and the ortho width will be its dimensions (by the way personally I set up a square render x=z). So if the ortho camera is (for example) 6491 y 1836 and your ortho width is 4500 (assuming that covers your entire island) then its rendered output will fall exactly at 6491 0 183 (position centre) with its "size" set to 4500 x 4500 and the projection set to "Plan Y".
Hope this helps
Richard

[Feyszar]

Hey cyphyr,
it worked very well now 
I see now why you set up square renders. In this way you don't have to care of the aspect ratio of the render/map.
Thanks a lot for your help !!