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POVTEX The Simple Texture Generator for POVRay. POVTEX 1.3a Designed and Programmed by Ted Wehner Documentation by Ted Wehner and Ken Freer 1 Disclaimer: POVTEX is provided as is, with no guarantee of its performance or compatibility. Neither Ted Wehner nor Ken Freer is responsible for any damage incurred by use or possession of this software. Use of POVTEX is at the user's own risk. Requirements: Microsoft(c) compatible mouse SVGA adapter (800x600x256) POVRay software Short Description: POVTEX v1.3a was created as an alternative to the manual creation of texture files using a standard text processor. POVTEX v1.3a came about after using many GUI modellers for POVRay that came with effective, though lacking, texture mappers. I felt that the need for a good, solid, easy to use texture creator was necessary. In checking the major bulletin boards, I discovered that there were no actual texture mappers, so I sat down one Saturday evening with a concept in mind. Here it is. Although it is easy to use, POVTEX can easily define an infinite number of textures. It does NOT, however, offer a tutorial on the usage of POV nor the effective use of mapping the actual textures into the edited files. It is not an intuitive designer, but an assistant to POVRay. The positive implications of POVTEX outnumber its limitations. One good thing: no more counting up those blasted braces and having POVRay scream at you with an error about "{ expected" and normal or something else like that. I have included all of that in the file creator. With all of that said and done, here is the rest of the documentation. (I guess that wasn't THAT short) 2 Table of Contents DEFAULT VALUES 3 PIGMENT 3 TEXTURE TYPE 3 GRADIENT X 3 GRADIENT Y 3 GRADIENT Z 3 MARBLE 3 WOOD 3 ONION 3 LEOPARD 4 GRANITE 4 BOZO 4 SPOTTED 4 MANDEL 4 RADIAL 4 CHECKER 4 HEXAGON 4 AGATE 4 COLOR MAP 5 Sliders 5 Transparency (filters) 5 Spread 5 Pigment Modifiers 5 NORMAL 6 BUMPS 6 DENTS 6 WRINKLES 6 RIPPLES 6 WAVES 6 NORMAL TURBULENCE 6 FINISH 7 DIFFUSE 7 AMBIENT 7 CRAND 7 BRILLIANCE 7 REFLECTION 7 REFRACTION 7 PHONG 7 SPECULAR 7 DISK / FILE FUNCTIONS 8 NEW 8 LOAD 8 SAVE 8 GEN 8 APPEND 8 3 Default Values All of the values are initially set to the default for POVRay when POVTEX is first loaded. Changes from this are for you to make if you choose, though they will remain the same if untouched. The documentation to follow does not describe the default values for this reason. The only values written to the .POV file will be those changes that you make from the default. Pigment Texture type There are 15 different texture types supported in POVTEX. There are others, but these are the least complex and most often used. These textures will give you the ease of creation and manipulation of the many colors, as simple or complex as you like The large button to the left of the screen is a selector. This will cycle through the 15 different textures in POVTEX. A brief description of these follow: GRADIENT X The gradient X has a color map progressing along the X axis of the POVRay coordinate system. This is similar to a gradient pattern with the "vertical stripes" in a left to right fashion. This color progression snaps back to the first color of the map at the end of the gradient. GRADIENT Y The gradient Y has a color map progressing along the Y axis of the POVRay coordinate system. This is similar to a gradient pattern with the "horizontal stripes" in a top to bottom fashion. This color progression snaps back to the first color of the map at the end of the gradient. GRADIENT Z The gradient Z has a color map progressing along the Z axis of the POVRay coordinate system. This is similar to a gradient pattern with the "horizontal stripes" in a front to back fashion. This color progression snaps back to the first color of the map at the end of the gradient. MARBLE The marble color map has a color progression that "ping pongs" from the first color to the last color. In essence, the color progresses forward, then reverses at the end of the texture. This is a smooth transition, unlike the gradients above that stop abruptly and begin again. For a true marble effect like you would expect in a rock, you will need to use a high turbulence setting. WOOD Like a tree, this textures forms concentric circles around the Z axis. It also "ping pongs" the color map. ONION Similar to the wood texture; however this one does NOT "ping pong" the color maps. 4 LEOPARD The leopard texture is fairly self-explanatory, unless you have never set foot into a zoo. The color map has spots of gradient color from the last half of the color map while the largest part is created from the first half. GRANITE Granite has its roots in the marble texture, but with a lot of webbing and intricacies that don't reverse. This is due to a noise function built into the granite texture. Play with this one. BOZO This texture is most often used for clouds. It take the noise function and maps it onto the surface of an object. The color map does not reverse. SPOTTED This one is the same as bozo, but turbulence does not affect it. MANDEL This texture uses the mandelbrot set for its mapping. If you are unfamiliar with a Mandelbrot set or have not heard of it, suffice it to say that it is complex in its use. I recommend getting a good book on it before you dive into this function. RADIAL The radial texture has a color map that wraps around the Y axis. The color radiates from the center and maps outward from there. CHECKER This is the checkerboard picnic tablecloth kind of texture. This uses two colors, one and two, in its scheme. They alternate and only touch the same colors on adjacent corners. HEXAGON This is similar to checker except that it uses three colors and maps them onto hexagons instead of squares. AGATE Agate texture is very similar to marble, however it is not affected by turbulence. Agate uses its own built-in turbulence function. It has a high degree of turbulence. Use in a well-ventilated room (just a joke). 5 Color Map The color map is the heart and soul of the textures. It is the engine of POVTEX. The color map represents the complete progression of colors in a single texture. The color map is represented by a series of ten boxes showing the colors of the current texture. Here, it needs to be noted that the colors shown are not the only colors that will be rendered in as a part of the texture. These are only reference points for you to use while creating your texture. POVRay will automatically interpolate the color values from these points. The two most important points would be the endpoints, while the intermediates are used mostly for those textures that have variances, such as multiple hues on a single texture. This is a really great area for experimentation. Sliders To edit the color maps, use the mouse to select the color to change. Use the sliders to change the values. The sliders are not "grab and drag," but are merely indicators for the actual values. Click above and below to change the values positive or negative, respectively. The number in the box below will reflect the percentage of hues being applied to the overall color. The selected box will adapt to those changes as well. You will see the true color you are creating for that area of the texture. Transparency (filters) Filters depict the amount of light that will pass through the texture from that point in the color map. Think of it as varying degrees of cellophane wrap over the image. For true transparency, you must have white color and 100% filter (not black as might be expected since all light must pass through). This is important for mapping clouds onto a background plane. Parts of the texture must be totally transparent while the remaining area is white with gray edges perhaps in order to allow light through. To change transparencies for a specific color, simply select the box below the color and type in the percentage of transparency. Spread The spreading of colors is to effectively make the gradient more smooth. This is used for filling in the color map between two color points. To spread colors, use the mouse to select the first color you wish to begin your spread. Use the mouse to then press the spread button. Finally, select the second color to be in your spread. The colors between the first and the second will then automatically spread to colors between the two. The filters will also be affected by the spread. Spreading can be done from anywhere on the color map and used more than once. A spread can be in any direction Pigment Modifiers There are several turbulence selectors, all of which affect the actual color map. Turbulence is the degree of perturbation of the mapping of the colors onto the object in POVRay. You can imagine this as the form of turbulence in the air or smearing a freshly painted canvas with your fingers. For descriptions of the octave, omega, and lambda modifiers, consult the POVRay manual. Frequency is the number of color map progressions within the unit cube space from zero to one of the POVRay coordinate system. Phase rotates the color map. 6 Normal Normal refers to the normal vector to the surface. This is the vector for each point that is perpendicular to the surface at that point. The normal modifiers actually distort these vectors so that the reflected light at these points produce the illusion of the many different surface textures that POVRay supports. The following surface textures are supported by POVTEX. After each is a brief descriptor of each. BUMPS Bumps are surface protrusions. The bump factor controls the height of the bumps. The bump scale controls the apparent width of the bumps. DENTS Dents are surface indentations. The function in a similar manner to bumps. The dent factor controls the depth of the dents. The dent scale controls the apparent width of the dents. WRINKLES Wrinkles are surface imperfections which create an effect similar to the furrows on wrinkled cellophane. Wrinkles scales controls the amount of wrinkling. The wrinkle scale controls the apparent size of the wrinkles. RIPPLES Ripples are surface modulations creating an effect of the surface of water after something small has been dropped into it. Ripples are generated from ten points within the unit cube space as if ten small stones had been dropped into the water. Ripple factor controls the amplitude of the ripples. The ripple scale controls the size of the ripples. Ripple frequency specifies the amount of rippling within a certain range. Ripple phase shifts the ripples within that space. WAVES Waves are surface modulations creating an effect similar to ripples except that the progression of ripples is not evenly spaced. It is a more realistic use of the ripple function. As the wave extends beyond the focus, the frequency decreases. The wave factor controls the amplitude of the waves. Wave scale controls the size of the waves. Wave frequency specifies the amount of wave effect within a certain range. Wave phase shifts the waves within that space. NORMAL TURBULENCE The normal turbulence is the degree of perturbation of the mapping of the surface texture onto the object in POVRay. Again, you can imagine this as the form of turbulence in the air or smearing a freshly painted canvas with your fingers, only this time with the actual surface, not the colors. For descriptions of the octave, omega, and lambda modifiers, consult the POVRay manual. Frequency is the number of surface map progressions within the unit cube space from zero to one of the POVRay coordinate system. Phase rotates the surface map. 7 Finish Diffuse The diffuse reflection controls how much light is reflected from the surface of the object. This represents the percentage of the light that is reflected from direct illumination. Think of it as how much light will be reflected off the object itself. Ambient Ambient light is the amount of light that is present in the area from all sources, the direct and reflected light. It comes from all directions and will be seen on any object that may be struck by this light. The amount of ambient light can be controlled with this feature. Crand The crand function controls the graininess of the surface. This simulates the small pits found in concrete, sand, etc. Note: the crand function operates on a pixel by pixel basis, so that objects in the distance will appear similar to foreground objects. Brilliance Brilliance controls the angle in which light hits the surface, creating the amount of shininess on the object. Surfaces may appear more metallic by adding brilliance. The default value is 1.0, where higher values from 3.0 to about 10.0 cause the light to fall off less. Reflection Reflection is fairly self-explanatory. The reflection controls the amount of reflection on the surface of an object, whether it be light from the light source or that of another object. Refraction Refraction refers to the bending of the light, direct and ambient, when passing through the surface of an object. The only values allowed are 0.0 for no refraction or 1.0 for refraction. This is best used with objects that are of glass or transparent textures. Phong Phong is the spot of reflected light that one usually sees on spheres from the direct light source. A phong value of 1.0 will saturate the object with the color of the light source at the center of this highlight. The phong size controls the size of the highlight. Larger values will yield a smaller, tighter spot. If you wish to have no phong on your objects, use an extremely high value. Typical values range from 1 to 250. Specular Specular is similar to phong, but it uses a more realistic function to model the highlight. The roughness value defines the size of the spot ranging from 0.0 to 1.0 with 1.0 being very rough and yielding a large highlight. 8 Disk / File Functions In the shareware version of POVTEX, the LOAD, SAVE, and APPEND features are disabled. You can still use NEW and GEN to create your files, though registering your product will allow you to fully exploit POVTEX. New New resets all values to their default. Path Path modifies the POVTEX.PTH file to your desired destinations for .INC and .PTX files. Load Load retrieves a POVTEX .ptx texture file from the drive. All values stored within this file will be loaded and applied to the current session. Save Save stores all of the values of the current session in a POVTEX exclusive format with the extension of .ptx. Gen Gen is short of generation; this command will generate an include file which can be called or used in a POVRay file. It can be called with an #include "filename.inc", where your filename will replace the "filename." Put the name of your texture in the texture block of the object for which you applied your texture. If the object does not already have a texture block, create one with the following lines, assuming the name of the texture to be BOB: object_name { pigment { texture {BOB} } } Note: All textures created in POVTEX are stored in allcaps and must be called as such. This is to differentiate your textures from those primitive to POVRay. Append Append performs the same function as GEN, but will append it to a previously saved .inc file. This effectively allows you to create your own library of textures.