(Generic) [Discussion] Seasons -- How to let it snow?

[Radagast.]

To make the units update their textures, .. e.g. turning on torch-/candle-light (by emission shader?) when night falls, putting more and more snow textures on the ground depending on how long it is is already winter, slowing down the units. I doubt that realtime snow falling from the sky will be possible as seen by computing power, so the only chance is to put an overlay animation over the whole camera lens if this works.

• The camera snow overlay might be the solution for the falling snow ... (each season should have an overlay and a transition animation? random? as it not snows all the time in winter?)

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• We have to solve another problem: heaps of snow. Particles are out of the question (performancewise).

  We could locally (to allow map variation) duplicate the terrain. The height simulates the 'grow' (i.e. increase snow height) by time.

  This ground layer has snow texture only and no objects.

  It's only visual. => Not possible to make light and small units like mice float ontop of the snow. (I could live with that. You?)

  So if you cross a mountain in winter it would rather be like passing the High Pass in the Misty Mountains when the fellowship was rather walking in the snow than ontop.

  As long as we have a speed-factor per pathfinder-tile we could at least make them slow down the more snow fell. (so it looks not too unrealistically)

  Adapting the height would depend on the unit's weight (per surface) & density, and it's not possible to adapt the unit height other than be animation or height map anyways. (and heightmap is out of the question as it heightens the objects, e.g. trees, plants, buildings ... on the terrain too! that's not what we'd expect.)

Edited April 13, 2014 by Hephaestion

[Stan`]

Do you remember how it was done in the Settlers V ? You had a weather machine (not accurate here), that could change the course of the battle with limited range when raining etc. Also another feature was that some types of water placed as a square map, could be frozen.

For the texture thing, a bump, and a snowy version is what you need.

[niektb]

Another option would be through snow shader:

http://unitygems.com/noobs-guide-shaders-2/

I only do not know if it would work performance wise (you have to ask the experienced shader programmers around)

[Radagast.]

Yeah, good idea, the shader - if it works out performancewise.

I have thought a bit about snow variation with altitude but I can't find a functional connection. Nor a diagram to derive the function from. So I guess we have to use a linear function first.

This is all what I could find, about snow height in The Swiss Alps:

http://link.springer.com/article/10.1023/A:1005310214361#page-1

Have posted in the Random map topic as the random map functionality had to be used for the creation of this visual snow layer too (to give it variation).

[BF_Tanks]

Could you not have all the ground and vegetation textures have a second layer which is the same but snow-covered, and then fade that texture in when it starts snowing?

[Radagast.]

Yes this was what I thought of too. This layer should have it's own height map - it should be able to vary, though it should be visual only first I guess.

Philip has once tweaked the terrain flattening purely visually in one of the C++-renderer classes. It's just too much for me to take at once currently. So I will try to tackle it one by one. (this one here will take years for sure as I'm no magician )

Thanks for sharing your ideas. I didn't think of the blending before.