A good way to create a river?

Blitz3D Forums/Blitz3D Beginners Area/A good way to create a river?

Azaratur

(Posted 2008) [#1]

Hi guys,
I need to create a river i tried with animated texture and i create a good sea effects..
But for the river is a little bit different it may do some "curves" and with animated texture is like the water go under the ground..
I need to create some wave in the right direction.. Have you any idea to do it?

Thanks

Aza

Moraldi

(Posted 2008) [#2]

Take a look here:
http://www.blitzbasic.com/Community/posts.php?topic=76749#858508
It is not about river, its about a waterfall. Turn it about 90 degrees and you got a river! :)

Warner

(Posted 2008) [#3]

How about using a curved mesh as a river ?

Graphics3D 800, 600, 0, 2
SetBuffer BackBuffer()

;create texture
water=CreateTexture(256,256)
Color 0, 0, 64
Rect 0, 0, 256, 256
Color 255,255,255
For j = 0 To 256 Step 10
For i = 0 To 256
Line i, Sin(i * 4) * 5 + j, i - 1, Sin((i - 1) * 4) * 5 + j
Next
Next
CopyRect 0,0,256,256,0,0,BackBuffer(),TextureBuffer(water)

;create river
mesh = CreateMesh()
s = CreateSurface(mesh)
For i = 0 To 30

	x1# = Sin(i * 12) / 4.0
	x2# = x1 + 0.5
	v# = (i / 30.0)
	y#=(i-15)/15.0
	
	If i > 0 Then
		v0 = AddVertex(s, x1, y, 0,0,v)
		v1 = AddVertex(s, x2, y, 0,1,v)
		v2 = AddVertex(s, ox2#, oy#, 0,1,ov#)
		v3 = AddVertex(s, ox1#, oy#, 0,0,ov#)
		AddTriangle s, v0,v1,v2 
		AddTriangle s, v0,v2,v3
	End If
	
	ox1#=x1#
	ox2#=x2#
	ov#=v
	oy#=y
	
Next
EntityTexture mesh,water
EntityFX mesh, 1

cam = CreateCamera()
MoveEntity cam, 0, 0, -2

t#=0
Repeat

	t=t+0.01
	PositionTexture water,0,t
	RenderWorld()
	Flip

Until KeyHit(1)

End

Ross C

(Posted 2008) [#4]

I would personally use a mesh too, with perhaps a scrolling texture, for moving water.

Stevie G

(Posted 2008) [#5]

Realistically, your landscape itself should already form the rivers shape. You probably only need an additive blended quad or plane with a texture.

Azaratur

(Posted 2008) [#6]

Thanks to all,
For Stevie G my landscape have the rivers shapes, i want do the river more realistic animating the water follwing the flow.

For Warner i'll try this tomorrow and i'll give you an answer.

For Moraldi i need this too :)

Aza

Ross C

(Posted 2008) [#7]

Problem with a plane with a texture, is the water will only run in the one direction. Where as a mesh that fits into the shape, can be unwrapped to allow a scrolling texture to flow the river along it's path.

Azaratur

(Posted 2008) [#8]

I try this and it work perfectly.
My last problem is that i precreated the shapes and if i try to create a river mesh with a 3d editor the texture scroll don't appear "natural" like creating from myself.
But creating it from myself is really difficoult because i don't see the shapes.. Maybe i can implement the mesh creator in my map editor.. Is it possible modify a mesh in real time?
Thanks to all for the moment

Aza

Warner

(Posted 2008) [#9]

You can modify a mesh realtime, with the VertexCoords command. However, you could search in your 3d editor for an uv mapping tool.

Azaratur

(Posted 2008) [#10]

I use uv map, but if i use plane or box mode texture scrolling didn't follow the flow.. If i use face mode it will follow the flow but it's not a unique texture..
My problem in the inner side of the curve the texture is moving too slow rather than in the out side. All appear like the water go under the face in front of that face
If i can i'll make a screenshoot for you.
Aza

Ross C

(Posted 2008) [#11]

You need to straighten the whole mesh out:


------
|    |
|    |
------
|    |
|    |
------

etc etc, instead of just doing a planar mapping, becausethe texture, if scrolled, will run down the axis. Think about the textures movement. And the way the mesh is laid out. The above should produce the correct result, all be it, slightly distorted. Shouldn't be too bad though.