Tutorial: Nebula Layers

Nebula layers are the most complex part of Space Generator, with controls split into sections to make them more approachable.

Basic Parameters

• Threshold
  The lower the threshold parameter the more of the screen will be filled with the nebula.

• Density
  Lower densities result in larger shapes, higher densities in tightly packed smaller shapes

• Alpha
  The opacity of the nebula layer.
  Note: this is a global multiplier - for instance, if a color in the chosen palette were at 50% opacity with Alpha set to 50% this color would be rendered at 25% opacity.

• Dither Enabled
  If enabled, dithering is applied at borders between colors in the chosen palette.
  Tip: if you want to reduce the amount of dithering between layers, consider increasing the weight of all colors a little!
  

Oscillation Parameters

• Oscillation Enabled
  Toggle the oscillation effect on or off.

• Oscillation Intensity
  The strength of the oscillation effect.

• Oscillation Rate
  The speed of the oscillations.

• Oscillation Offset
  Offset the location in the current oscillation cycle - primarily provided as a way to offset two layers with the same oscillation rate.

Modulation Parameters

A note here on how Modulation settings work: modulation is based upon a secondary noise texture, the brightness of which is used to adjust characteristics of the main nebula texture. This can be used to affect the color of the nebula, its opacity, or both simultaneously.

• Mod Color
  The base color of the modulation layer.

• Mod Intensity
  How strong the effect of the color modulation should be. Higher values will result in the final color being shifted more towards mod color.

• Mod Alpha
  How strong the effect of alpha modulation should be.

• Mod Density
  Lower densities result in larger shapes, higher densities in tightly packed smaller shapes.

• Mod Steps
  The modulation noise layer is quantised into discreet bands of brightness - this setting controls how many bands are used. Lower values result in a more obviously stepped effect, higher values are still visibly stepped but look closer to a smooth gradient.
  Note: I chose to restrict modulation to steps to give the impression of a more limited palette in line with typical expectations for pixel art - if you'd prefer to allow smooth gradients this would be a simple enough change to the nebula shader!
  

Layer Settings

• Scroll Speed
  The speed at which the layer scrolls across the screen.