bhodiNUT Fresnel v1.0 Documentation
 ©1999-2000

Installation: Copy the bhodiNUT Fresnel folder into the Cinema 4D plugins folder. The installation is complete. Launch C4D and the FRESNEL channel shader should be available under the "bhodiNUT Channel Shaders" hiearchial menu item within the channel shaders menu.

Usage: The Fresnel shader is used in any of the channels of a material. It has no effect upon the bump channel or the displacement channel unless utilized as a secondary channel within bhodiNUT FUSION or something similiar. The shader calculates the falloff of the surface normal in world space from the incoming surface ray which is also in world space. Then it utilizes the parameters of the shader to attenuate the output.

Parameters:

The gradient is a standard implementation of a color gradient. To change the color of a knot double click it. To invert the order of knots use command-I on the Macintosh and control-I on the PC. To remove a knot drag it off the gradient. You are currently limited to fifty knots.

  Position: if the position of the currently selected knot or bias handle. You can type a value in the edit text field or drag the up/down arrows at the right.

Interpolation: Is the interpolation type of the knots. Cubic Knot: Interpolates the knots with a CatMull - Rom interpolation while using the bias handles to offset the interpolated value ( Good for several knots ).

  Cubic Bias: Uses a Bezier interpolation algorithm to interpolate between the knot previous to the sample point, a weighted bias to the left, a weighted bias to the right, and the knot to the right of the sample position ( Good for few knots and accurate control ).

Smooth: Uses a SmoothStep function to weight an interpolation between the knot to the left of the sample point and the knot to the right of the sample point. It uses the bias handles to offset the interpolated value.

Linear: Uses a BoxStep function to weight an interpolation between the knot to the left of the sample point and the knot to the right of the sample point. It uses the bias handles to offset the interpolated value.

None: Uses the color of the knot to the left of the sample point.

Use Bump: Dictates whether the output of the bump channel will be used in the calculation of the falloff.

Render: This is a fairly complicated parameter. Front Only: Calculates the falloff for the front of the object and then sets the back of the object to black if it can be seen. Front Only - Trans: Calculates the falloff for the front of the object and then sets the back of the object to white if it can be seen ( Good for use in the transparency channel ). Back Only: Calculates the falloff for the back of the object and then sets the front of the object to black if it can be seen. Back Only - Trans: Calculates the falloff for the back of the object and then sets the front of the object to white if it can be seen. Front & Back: Calculates the falloff for all surfaces intercepted.

Features that apply to all of the shaders: ( Macintosh / Windows )
  Copy Parameters: Command-Option-C / Control-Shift-C

Paste Parameters: Command-Option-V / Control-Shift-V

Revert Parameters: Command-R / Control-R

Reset Parameters: Command-Option-R / Control-Shift-R

For FRESNEL you can now change the preview type and turn on and off anti-aliasing for the rendered previews using the combo box and the checkbox under the preview.

This shader is considered a commercial product and released to Cinema4D users at no cost. There is no implied warranty, nor do we accept any liability for software failure.