| TG InfinitePlane Cloud |

| PARAMETERS |

| Listing : Sunlight Vector Cloud Plane Height Begin Fade Distance End Fade Distance Horizon Offset Ambient Light Intensity Sunlight Intensity Ground Light Intensity Cloud Cutoff Exaggerate Cloud Displacement Cloud Frequency Octaves Displacement Offset Sky Colour Cloud Colour Haze Colour Ambient Light Colour Sunlight Colour Ground Light Colour |

| Test Scene To fully illustrate what the shader does, on the left is a wireframe screen grab of the test scene used to produce the sample images for each parameter. The screen grab is done from the standard side view in trueSpace, and all test renders on this page are done from this set-up, from the camera shown in this image. Note that the sky is painted on a cube - you could use a sphere, or any shape you like really, as it makes no difference to the end result (neither does the scaling of the object - note how the cube here is only fractionally larger than the scene it surrounds). |

| These points immediately illustrate several advantages to this shader. First, poly counts are kept low as you can use any shape you like. Second, it becomes easier to manage the scene, in part because the size of the sky object makes no difference (and also because it can sometimes be hard to judge just when a sky sphere was large enough to encompass those mountains without them sticking through the edges.....a lot easier with a cube). Third, it used to be that if you scaled or stretched the sky object, the noise pattern could well scale or stretch with it - not so with this shader, since your clouds are viewed on the virtual infinite plane, and the sky object only acts as the “window” through which you view this plane. Stretch it in any way you like, and the noise pattern remains consistent. |

| Sunlight Vector Range : -100 to 100 for each sub-parameter The clouds are artificially lit by several light sources. This parameter controls the direction that the sunlight effect is coming from, by setting the point in world space that the light is pointing toward - simply imagine that the sunlight is an infinite light positioned at the origin in the scene (in world space), and is pointing at the position set by this parameter. The sample scenes below use extreme values in the x direction to show the results - the light is pointing toward the left in the leftmost image, so the right hand edges of the clouds are illuminated, whereas the light is pointing toward the right in the rightmost image, so that the left hand edges of the clouds are illuminated. Note that in both cases the light is pointing upward slightly, with a z of 0.1. The cloud simulation is the more accurately the simulation of the base of the clouds, as if they were displaced from the surface of the infinite plane, and so illumination from above (a negative z value for the Sunlight Vector) will not necessarily show up very well - as always, however, experimentation is the order of the day! |

| Sunlight Vector of (100, 0, 0.1)
| Sunlight Vector of (-100,0, 0.1) |

| Two rather extreme settings for the Sunlight Vector |

| Cloud Plane Height Range : -320 to 320 Adjust the height of the virtual infinite plane. This controls the appearance of the sky by setting how high up the clouds are, which has several effects. First, the frequency of the clouds appears to alter, as the higher the cloud plane, then the smaller and more dense the clouds appear, and the lower the cloud plane, then the larger the clouds are nearby (they still scale to small in the distance, of course). Second, the horizon appears to change, as the fade distance will alter, becoming harsher or more spread out depending. Note that this is a real setting - in animations, when the camera moves, as the z of the camera nears the cloud plane height, so the frequency of the clouds will change, and when the camera exceeds the cloud plane height, the clouds will appear BELOW the camera rather than above. Similarly, setting a negative cloud plane height (or one which is lower than the camera’s z position anyway) will result in clouds appearing beneath the camera, like an infinite sea or ground plane. |

| Cloud Plane Height of 5 ( the default)
| Cloud Plane Height of 2
| Cloud Plane Height of 10 |
| Cloud Plane Height of 0 (chequered plane made temporarily invisible in this render) |

| Begin Fade Distance and End Fade Distance Range : 0 to 3200 Every good sky fades with distance (as does every good landscape), owing to haze in the atmosphere. Since it would be impossible to use trueSpace fog or depth cue to do this (as the infinite plane is virtual and not really in the scene - the distances used would be from the camera to the sky object, which is not what we would want!), the shader comes with its own inbuilt depth cue. Note that both distances refer to the distance to the point on the virtual infinite plane, NOT to the distances to the sky object. For example, under ordinary circumstances, points close to the centre of the screen (at the horizon) will be VERY far away indeed. The Begin Fade Distance sets the distance at which the fade of the sky (the sky and the clouds, that is) to the Haze colour begins. The End Fade Distance sets the distance at which the colour becomes entirely the Haze colour and nothing else. This parameter will affect the apparent height of the “horizon line” too. |

| End Fade Distance set to 2000 (everything else default), showing just how far the infinite plane stretches! |

| Horizon Offset Range : -20 to 20 It’s all very well having an infinite plane at a set height, but sometimes when you have the clouds looking just the way you want, and the fade points just so, you’ll find that the horizon is too high or too low for your scene - it may well be “accurate” as to where the horizon would appear, but you still want a quick and easy way of adjusting the apparent height of the horizon line (when the sky fades entirely to the haze colour), in order to get it to match your scene set up. This parameter lets you do that by “cheating” the effect of the shader. A negative value will lower the horizon line, while a positive value will raise it. Note that values should lie between -1 and 1; values outside of this range have been permitted for unusual effects. The further this parameter is from 0, the more distortions you will see in the horizon line and in the noise pattern (the horizon will become more circular or rounded, rather than straight). At values of greater than 1 or less than negative 1, the clouds will cease to appear as a flat horizontal plane, but look more like an angled or even a vertical plane, stretching in unusual ways (not so useful for making skies and backgrounds, but could generate some interesting noise patterns, which is why the values have been permitted). Bear in mind that keeping this value close to 0 is probably best if you are after “sensible” results...! |

| Horizon Offset 0.06
| Horizon Offset of -2 |

| Ambient Intensity, Sunlight Intensity and Ground Light Intensity Range : 0 to 1 (ambient); 0 to 50 (sunlight); 0 to 10 (ground) These three parameters control the strength of each of the light sources that are used to colour the clouds. Note that these light sources ONLY illuminate points that are classed as clouds - points that are classed as sky (or haze) are NOT affected by these parameters. The Ambient Light illuminates the entire cloud equally, just like the ambient setting in an ordinary trueSpace shader (and just like that setting, this lighting does not care which direction the surface is pointing in). The Sunlight illuminates the cloud from the direction set by the Sunlight Vector, while the Ground Light illuminates the cloud from a vector pointing straight up from below (representing light reflected from the ground). |

| Cloud Cutoff Range : 0 to 1 This value controls which point counts as part of a “cloud” and which point counts as part of the “sky”. The lower this value, then the more points will be classed as being “cloud”, resulting in larger, fuller clouds. The higher this value is set, the smaller and wispier the clouds will be. |
| Exaggerate Cloud Displacement Range : 0 to 320 This controls the simulated displacement that happens for the clouds. Higher values results in greater displacement, increasing the effect of the direction of the lightsources. Note that the displacement is simulated, and only affects the lightsources within the shader, and does not result in conventional displacement that responds to tS lighting (since the infinite plane is only virtual, and doesn’t actually exist within the tS environment......) Very high values will result in extremely artificial and abstract effects, which can still be fun to play with. |
| Cloud Frequency Range : 0 to 100 Sets the frequency of the clouds - that is, the frequency of the noise used to generate the clouds. Higher values mean more, and smaller, clouds, while lower values mean less, and larger, clouds. |
| Octaves Range : 0 to 10 Controls the octaves used in the noise that generates the clouds. Lower values will result in smoother, more plain clouds, while higher values will result in more detailed (crinkly, wispy, etc) clouds. |
| Displacement Offset Range : 0 to 1 The simulated displacement compares the noise values for several points on the surface to determine the direction the surface is facing in at any given point. This parameter controls the gap between the points used for the comparison - very small values will give less of a noticeable effect, but more accurate, while large values will give more noticeable effects but which may be more unusual and less accurate. A value of 0 will disable the simulated displacement, thus disabling the lighting effects. |
| Sky Colour, Cloud Colour, Haze Colour, Ambient Colour, Sunlight Colour, Ground Light Colour Range : RGB values These parameters control the colours that are used to generate the final sky effect. The first three control the base colours of the Sky, the Clouds and the Haze, while the final three control the colours of the light sources (which only affect the Clouds). |
| TG InfinitePlane Cloud Intro |
| TG InfinitePlane Cloud Parameters |
| TG InfinitePlane Cloud Tips |
| TG InfinitePlane Cloud Samples |
| TG Pack 2 Index |