If I'm the man to talk to, I don't know as this is new for me too
but...I do have ideas though.
So you can't export to a heightfield, so let's try to make a heightfield from your .obj
TG2 reads .obj files, but not 3ds (but you can easily convert other object standards to .obj, usually).
(I don't know if sketchup also exports textures. I'd add one texture, a plain color suffices, in order to create a texture channel which will show up automatically in TG2.)
Load the object in TG2 (top section called "objects" choose "load object" then "obj loader" and navigate to your exported terrain .obj file.
By default it is positioned at the "origin" which means position 0,0,0. Keep it there.
See if the scale of the model is correct. You can check this by using the measure tool, which you can find at the top of the preview render. It's a yellow measure.
If it doesn't have the right scale then adjust that in the object settings. For that, click on the object in object panel on the left.
You will see "translate" "rotate" and "scale" settings. Change the scaling accordingly for each axis.
To shade the object as a heightfield we need a function that gives black color at the bottom and white color at the top of the terrain.
We'll use a distance shader for this.
Go inside the internal network of your object. It's a symbol with 3 tiny squares, one at the top with 2 linked to it at the bottom.
Repeat that step until you can't go further.
You should see a "parts shader" now with a "default shader" attached to it (a grey node with a red one attached to it on top).
Now right click with the mouse and chose "create shader -> colour shader -> distance shader".
Create a camera by right click with mouse "create other -> create camera" and place the camera at coordinate 0,0,0.
The second line shows the rotations, enter 90, 0, 0 there. The camera is now facing straight up.
Double-click on the distance shader. You'll see a "far distance" and "near distance" setting.
Change the default 10000 to 0 and the 0 to the actual height of your model in metres.
To know the models altitude in metres you will need to finish the preview render completely and make sure you can see the highest point of your terrain.
Then hover with the mouse on the highest point and at the bottom of the preview render you can find the coordinates which correspond to the position.
The Y-value is the altitude. Note this value and enter that as value to replace "0" for near colour.
Choose z-depth instead of spherical.
Choose the new camera as distance camera.
Since the new camera faces upwards the distance shader will create a b&w gradient in the direction the camera is facing. Important!
The gradient is now black at 0 metres from the camera and white at x metres, where x means the altitude you measured in the preview render.
Now you've set up your distance shader and connect it in between the red and grey nodes (of the "parts shader").
Your model will now be vertically shaded.
Go to your original render camera and position it at 0, 1000, 0. For rotation enter -90, 0, 0.
The render camera now faces down at an altitude of 1000m.
Reset preview render and have it finished. The 1000m might be too much or not enough. Change accordingly.
Go to the lighting section and change the sun's elevation to 90 degrees.
Go to the render-tab and go to full render. Set render-size to a square formatted image, say 1000x1000 pixels.
Switch off "render atmosphere" and "render shadows".
Reset preview render and let it finish again.
You should now see a greyscale shaded version of your terrain.
Hit render and save the file as .bmp.
Crop the unwanted edges from your file in photoshop/GIMP/whatever (if applicable).
Save the file as .bmp.
Start a new project in TG2 and go to the terrain tab.
Choose "create heightfield -> heightfield load" and navigate to the .bmp file.
In the network you see 2 new nodes in the terrain group. A green one (heightfield load) which loads the .bmp and a red one (heightfield shader) which creates the heightfield.
Right click with mouse and choose "create heightfield operator -> heightfield resize" and link the new node in between the green and red node.
Double click on it and set the "resize to metres" value to your desired dimensions.
Now you should have a terrain inside TG2 which is capable of being displaced, textured and populated with grasses and trees. And water, and clouds
Ok, a long piece of text here, please let me know how it goes and report back here.
I did this all straight from my head so I might have missed some little things.
Cheers,
Martin
