A possible problem was noted by Cyril Brulebois regarding copyright issues

with regards to the noise functions in yafray based on Ken Musgrave's
original code.
I had left the 'Copyright' notice in the comments, and according to
Cyril Brulebois this is a problem. In fact, from what I understand this
makes it even impossible to use or modify the code in other software.
But since it is not a verbatim copy of the code but rather based on Musgrave's
work, he suggested I change it to explicitely state that it is in fact
based on the code from the 'Texturing & Modeling' book.
And since the yafray code is in turn based on the blender code, I better
adapt the blender code too.

This reminded me that I also have forgotten to include the copyright notice
in the mersenne twister rng code I used for the Python Noise module.
This does clearly state to include the original notice with any resdistributed
code, in modified form or not. So I added that too.

I hope that solves the problems.

1 files changed, 4 insertions, 20 deletions

diff --git a/source/blender/blenlib/intern/noise.c b/source/blender/blenlib/intern/noise.c
index 3a2dd12a804..4fa2d1fdd48 100644
--- a/source/blender/blenlib/intern/noise.c
+++ b/source/blender/blenlib/intern/noise.c
@@ -946,20 +946,14 @@ float BLI_gTurbulence(float noisesize, float x, float y, float z, int oct, int h
 }
 
 
-/*************************************/
-/*  NOISE FUNCTIONS BY KEN MUSGRAVE  */
-/* Copyright 1994 F. Kenton Musgrave */
-/*************************************/
-
-/* All of these are modified to be able to use them with different noisebasis.
-   In some cases the original code seemed to contain errors, so it is not exactly
-   the same now as the orginal code (from "Texturing and Modelling: A procedural approach") */
+/*
+ * The following code is based on Ken Musgrave's explanations and sample
+ * source code in the book "Texturing and Modelling: A procedural approach"
+ */
 
 /*
  * Procedural fBm evaluated at "point"; returns value stored in "value".
  *
- * Copyright 1994 F. Kenton Musgrave
- *
  * Parameters:
  *    ``H''  is the fractal increment parameter
  *    ``lacunarity''  is the gap between successive frequencies
@@ -1025,8 +1019,6 @@ float mg_fBm(float x, float y, float z, float H, float lacunarity, float octaves
  * Procedural multifractal evaluated at "point";
  * returns value stored in "value".
  *
- * Copyright 1994 F. Kenton Musgrave
- *
  * Parameters:
  *    ``H''  determines the highest fractal dimension
  *    ``lacunarity''  is gap between successive frequencies
@@ -1094,8 +1086,6 @@ float mg_MultiFractal(float x, float y, float z, float H, float lacunarity, floa
  * Heterogeneous procedural terrain function: stats by altitude method.
  * Evaluated at "point"; returns value stored in "value".
  *
- * Copyright 1994 F. Kenton Musgrave
- *
  * Parameters:
  *       ``H''  determines the fractal dimension of the roughest areas
  *       ``lacunarity''  is the gap between successive frequencies
@@ -1170,8 +1160,6 @@ float mg_HeteroTerrain(float x, float y, float z, float H, float lacunarity, flo
 
 /* Hybrid additive/multiplicative multifractal terrain model.
  *
- * Copyright 1994 F. Kenton Musgrave
- *
  * Some good parameter values to start with:
  *
  *      H:           0.25
@@ -1246,8 +1234,6 @@ float mg_HybridMultiFractal(float x, float y, float z, float H, float lacunarity
 
 /* Ridged multifractal terrain model.
  *
- * Copyright 1994 F. Kenton Musgrave
- *
  * Some good parameter values to start with:
  *
  *      H:           1.0
@@ -1319,8 +1305,6 @@ float mg_RidgedMultiFractal(float x, float y, float z, float H, float lacunarity
 
 /* "Variable Lacunarity Noise"
  * A distorted variety of Perlin noise.
- *
- * Copyright 1994 F. Kenton Musgrave
  */
 float mg_VLNoise(float x, float y, float z, float distortion, int nbas1, int nbas2)
 {