Part 2: Ttexturing the river

2. Let's start on the surfaces. Open the Surfaces panel and select the RiverAndFalls surface.  We want a darkish blue-green color for the river surface.  Set the surface color to 48, 90, 100.  Remember the theory about setting up different sub-surfaces as vertical layers.  Let's see if it works.  Let's add another color that should only beapplied to the waterfall.  Click the 'T' button next to the Surface Color and select Grid.  Set the color to 238, 240, 242 and set the Line Thickness to 1.0.  The texture size should be left at 1 meters for all axis.  This will give us an all white texture.  Well blueish white.  Now for the trick:  Set the Texture Center to -10 centimeter.  Remember that this was the Y-coordinate for the waterfall polygons in the RiverSource object. 

As it stands now, the whole object will be white.  We want the white color to affect the waterfall and to fall off until it does not have any effect on the river polygons at Y=0.  To do this, we need to set a Texture Falloff value for the Y-axisi.  If we set this to 100, the texture will fall off over 1 meter.  We want 10 centimeters, so we need to set it to 1000. 

Set the Specular Level to 100 and the Glossiness to Medium.  While we're at it, lets set up the first layer of bump maps, too.  Open the Bump Map panel and select the Crumple texture.  Crumple is often good for water.  Set the texture Amplitude to 100, Number of Scales to 4 and Small Power to 0.75.  This is running water, so the waves should be long.  Set the texture Size to X=15 m, Y=1 m and Z=2 m.  To restrict these bumps to the River surface, leave the Texture Center at Y=0 meters and set the Texture Falloff for the Y-axis to 1000. 

Set up the camera so that you have a good view of the waterfall edge and render.  You should get something like this: 

I've set up my key light from the back right.  To see the river better, I've added a light from back left to get some specular highlights on the surface. 

As you can see, the layered texturing is indeed working.  The river surface has the blue/green color and the bumps.  The waterfall is white and does not have any bumps. 

3. Let us introduce some variation to the colors.  Open the Texture panel for the Surface Color and click on the 'Add New Texture' button.  Select Fractal Noise as the texture Type.  We want to add some variations to the River surface, so make sure the Texture Center is set to 0 meters on the Y-axis and set the Y-falloff to 1000.  Set the Texture Size to 10 meters on all axes and raise the Small Power to 1.0. Set the color to 50, 80, 110.  Lower the Texture Opacity to 50. 

4. Now let's do something to that smooth waterfall.  We will use a Crumple bump map to break that up, too, but this time we will use a negative amplitude.  Open the Bump Map panel.  You should see the River bumps.  Click the 'Add New Texture' button and select Crumple.  Set the texture Size to X=30 m, Y=3 m and Z=3 m.  Set the Texture Amplitude to -100, Number of Scales to 2 and Small Power to 0.6.  Again, to restrict this to the waterfall, set the Texture Center to Y= -10 cmand set the Texture Falloff to Y=1000 . 

Close the panel and render. 

5. That gave some definition to the waterfall, but the 'lumps of water' are still smooth.  Lets make som froth.  Open the Bump Mao panel again and press the 'Next texture' button to get to the waterfall texture that we just applied.  press the 'New Texture' button and select Fractal Bumps as the Texture Type.  Set the size to X=1 m, Y=10cm and Z=10cm, set the Texture Amplitude to 100 and the Frequencies to 6.  Set the Texture Center to Y= -10 cm and the Texture Falloff to Y=1000. 

Another render reveals a much more chaotic waterfall. 

 6. We have not set reflection parameters yet.  Set Reflectivity to 80.  The waterfall complicates things a bit.  We do not want the waterfall to reflect.  We deal with this as we did with the color.  Press the 'T' button next to the Reflectivity value and set the Texture value to Grid.  Set Texture Value to 0 and Line Thicknes to 1 m.  Set Texture Center to Y = -10 cm and Texture Falloff to Y=1000.  Also, in the first shader plug-ins slot unsder the Advanced Options tab, select LW_FastFresnel. 

Now, what to reflect?  I have used cube with a SkyTracer generated warp images.  You could also use a sperical reflection map using a suitable sky image.  A render of the new surface should look something like this: