Note: For your convenience, these example objects and scenes are included on the release CD in the 'Tutorials' directory.

In it's most basic application, the High Tide plugin allows a suface that it is applied to, to become "soft". The amount of softness - which we'll call depth - is user defined and may be defined either by a single number (ie. 10 meters), or by the use of an image map to vary the degree of depth across the surface.

This tutorial will demonstrate it's use by creating a simple scene consisting of a four walled room and placing a single flat plane with the high tide plugin applied. We'll create a volumetric like appearance without the processing time involved in using volumetrics. The other benefit will be that the High Tide surface will an image map applied to it, something not possible with current volumetric objects.

In Modeler, create a box 20 x 20 meters wide, and 10 meters tall.

On a second layer, with the first visible but inactive, create another box that fits snugly within the first box on all sides. Switch back to the first layer and with the second layer visible but inactive, do a boolean subtract. This will carve out the first box with the smaller one. Apply a surface to this new shape and called it "walls".

Next, use the polygon tool and select the polygon that would become the floor surface. (This would be second polygon from the bottom if seen from the front or side view) Create a new surface for this and call it "Floor" - also, give it a light brown color.

Let's add four window openings in this model next. One a new layer with the first one inactive but visible, create box as shown in Figure 4. Make sure to place the bottom of the new box slightly above the floor plane in the original object (see figure 4 again). This does two things: creates a threshold for the room opening, and more importantly prevents strange and unwanted boolean operations from taking place.

Go back to the first layer, and do a boolean subtract with the box you just created. Two openings should appear on either side of the wall/floor object. Next, go back to the layer with the small box you just created, and rotate it 90 degrees. Switch back to the first layer with the main wall/floor object, and again, do a boolean subtract. That's it for the room object. Save it out to layout.

Now, let's create a flat plane for the High Tide object. Apply a new surface to it calledt "High Tide", and export the object out to layout ..

From the top view, place the camera just inside the opening of the wall object as shown and change the camera zoom factor to about 2 (15 mm). and make the light a point light and place it similar to shown below (the light is the little star object in the south-west corner of the room, to the left and above the camera in the image below) When switching back to Camera view mode, chances are what will happen is that your view will be pretty much obscured by the High Tide object but don't worry about it at the moment.

Select the High Tide surface and make the primary color white. Then, apply a fractal noise texture with a size of 1,1,1 and make the noise a deep orange.

Goto the advanced options panel for the High Tide surface and apply the High Tide shader. Click on the "options" panel and adjust the settings as shown...

The Amount controls how much of the effect is applied - generally, you always want it at 100%. The Depth represents how deep the effect "can" appear. With no further adjustments (ie, applying an image map), this is an absolute number and the number you put in here simply represents how deep and object can go through the surface before it disappears entirely.

Things that will modify this depth setting are when you apply an image map. The number still represents the depth, but now it's an overall figure because the image map's greyscale values will modify the depth across the surface within the boundaries specifed by the "Depth".

Now, let's apply the cloud texture supplied with this tutorial. Click on the "Depth Map" button and load in the cloudgrey image for this tutorial. Apply the settings as shown...

Figure 9.

Doing a quick render, assuming your camera and lights are positioned similar to above, will yield a result similar to this..

Adding the "Cylinder" object from the High Tide tutorial folder, and turning on raytrace and shadow options will demonstrate the effect more clearly as the cylinders will merge right into the High Tide plane object and create a fairly dramatic effect.

Let's take a look at the effects of changing the depth parameter.

Adjusting the "Depth" in the high Tide surface to 5 shows us much less of what's behind the polygon.
Removing the Depth Map and just using an absolute depth of 5 would give a very even effect. Note especially the ground area much more even edge (notice the ground area) to the smoke effect.

Depth = 25	Depth = 5	No Depth Map

When using High tide in conjuction with raytracing and/or lights that cast shadows, it's important in certain situations to turn off shadow casting abilities and occasionally shadow receiving abilities for any object with High Tide applied as it's primary surface. In the above example, if shadow castig had been on for the High Tide object, because the surface is still, in reality, a solid object, it would have cast a solid shadow, which is not what you want obviously. Different scenes will require experimentation to see which features can be left on.