Terrain tiles perspective merging

[franciscod]

Let's say i have the following terrain texture made by A Bad Guy (notice the colour dots in the alpha space)

The alpha space is outside the rhombus, so it'd be okay... right?

NOPE! THE DOTS TRY TO REACH GABEN!

Basically each tile wastes half the space.

We should fix this 😀

[lilezek]

Does anyone what those dots are made for? Is it a bug from the media conversion? Or there are there in the original AOE?

[franciscod]

i put them on the terrain file just for checking this bug :D

[mic-e]

Hm... mmmaybe it's your own fault for placing the dots in the first place.

Regardless, speaking about terrain-preprocessing, maybe it would be best to store the terrain as one single rhombus.

[franciscod]

that is a valid point too: we want to allow the modders to overflow the
conventional rhombus like i did with the dots?

[TheJJ]

Currently, half the space is wasted for drawing the terrain. I'd really like to merge the texture to one square sprite which is then rendered in perspective to achieve the rhombus form again. This whould allow rendering same terrain areas with the same texture and even make use of the texture-unit's overflow wrapper that just repeats the texture.

[mic-e]

I don't think we'll be able to achieve the pixel-by-pixel stock look with perspective rendering.

[mic-e]

[franciscod]

nice idea mic-e!

[goto-bus-stop]

I'd really like to merge the texture to one square sprite which is then rendered in perspective to achieve the rhombus form again.

This is exactly what HD Edition does: (although it does ship with the old, now unused terrain.drs)

[lilezek]

@goto-bus-stop As mic-e said in irc, the goal is avoiding the need of applying any transform. With his example (the image with the drawing) you need to cut the texture, but you don't need to apply any other transform.

[TheJJ]

We could do perspective rendering of the terrain in theory with the new renderer (#287), but i'll try to implement the single-quad idea. Otherwise we'd have to transform the original terrain tiles to be non-perspective to render them perspectively again later.
Perspective rendering would be required though once aoe:hd removes the legacy files and just ships the terrain textures directly (which will happen one day..)

So I'll prepare perspective terrain rendering (but for that the coordinate system has to be improved..) but implement the above squaring of the terrain tiles.

Then again, to implement the terrain blending in the shader efficiently, rendering the terrain as a non-perspective plane makes it much easier to split at tile boundaries. Rendering the resulting fragments perspectively makes it look right again but is no more effort then.

[heinezen]

Implemented in #1497