A grass_impostor_base material is used for impostors. It can be applied to grass objects that, in turn, can be used as impostors for trees.
Auxiliary rendering pass is used for writing an additional texture into an auxiliary color buffer. Detail information on the pass can be found in the Rendering Sequence article. The pass can be used for custom post-process effects.
Noise activates spatial color noise texture, so the grass is colored according to it. The noise texture can add irregularity to the color of the grass field or it can color the grass.
Ambient Occlusion enables the ambient occlusion that sets shading arising from the ground to the top of the grass blade.
Normal Map enables the normal map for the grass impostors. This option is used to fake the relief on the impostor surface.
Lerp enables smooth linear interpolation of sprites when the camera rotates around the object.
Up Direction makes impostors always pointing upwards.
Animation option enables animation for objects (e.g. for plants swinging in the wind). Available modes:
- None - animation is disabled.
- Animation - standard animation is used.
Standard Animation of Impostors
- Field Animation - standard animation is used together with animation produced by Field Animation.
Standard Animation of Impostors + Field Animation
Jitter Transparency enables creating deferred transparency by using jittering. The state can be used when such result is acceptable and post-effects are applied to the material.
Mip Bias activates an additional mip bias parameter. It is used to adjust mip mapping.
Material SSAO enables screen space ambient occlusion.
Material SSR enables screen space reflections.
Material SSS enables subsurface scattering.
Material DOF enables the depth of field effect.
Material Motion Blur
Material Motion Blur enables the motion blur effect.
Material Sun Shafts
Material Sun Shafts enables sun shafts.
Textures available for the material. All of the textures fields have set default textures, which can be replaced by your own ones. Availability of some textures depends on the set States values.
Normal texture of the grass impostor. The texture is used to fake the relief on the impostor surface. To create a normal texture for impostor, use Impostors Creator tool.
Auxiliary texture is used for auxiliary rendering pass.
Noise texture is used to color the grass (for example, to match the colors of the terrain) or to add irregularity to the color of the grass field. In both cases, the colors of the grass diffuse texture and the spatial noise texture are blended in the overlay mode.
The texture is 3-channelled (RGB).
Visibility Mask Texture
Visibility Mask texture is used to cut out grass.
The texture is 1-channelled (R).
- R - visibility mask.
Availability of some parameters depends on the set States field values.
Material Mask parameter specifies a decal bit-mask. If the material mask of the decal material matches the material mask of the surface material, the decal will be projected.
Base Shading Parameters
Diffuse texture color is the base color of the grass impostor surface.
Specular is a color picker to choose the auxiliary specular color. It can be used for specifying different specular colors for one texture or modifying the texture color on the spot.
Gloss is a coefficient modifying the size of the highlight.
- Low values imitate wider highlights, typically appropriate to create diffuse reflection from mat surfaces.
- High values imitate pinpoint highlights, typically appropriate to create uniform reflection of light rays from glossy surfaces.
Microfiber is a coefficient to scale the intensity of the microfiber effect. This parameter creates an effect of the napped surface. The higher the value, the higher the microfiber effect is.
Translucent is a coefficient to scale the translucent effect, which permits light to pass through the grass blades, but diffuses it so objects behind the grass blades are not visible. The higher the value, the more translucent the material is.
Alpha Intensity is a coefficient to scale the value of the alpha channel of the grass diffuse texture. The higher the value, the bigger areas of the texture are rendered.
Shadow Offset sets an offset of grass impostors shadows.
Impostor Coordinates specifies impostor texture coordinates transformation.
Mip Bias is a coefficient for mip maps adjusting.
Stem noise is a coefficient to scale a spatial noise that diversifies the direction of movement of the grass.
- 0 makes the grass move uniformly.
- Increasing the value makes the grass blades movement more random.
Stem offset is a coefficient to scale an amplitude of horizontal movement of the grass.
Stem radius is a coefficient to scale an amplitude of vertical movement of the grass.
Stem scale is a coefficient to scale the speed of grass movement.
Ambient Occlusion Parameters
Visibility specifies how the AO has influence on grass.
Multiplier is a coefficient to scale the occlusion that sets shading starting from the ground to the top of the grass blades. The higher the value, the less shaded the grass is.
Power is the rate of ambient occlusion appearance on the grass.
Impact On Diffuse
Impact On Diffuse shows how ambient occlusion affects the grass diffuse texture.
Transform specifies spatial noise texture coordinates transformation.
Scale is a coefficient to scale intensity of the spatial noise texture.