DRM Settings & Editor Window
Before using DRM inside shader appropriate DRM effect needs to be generated inside editor. It is done by using DRM editor window from Unity Main Toolbar → Window → Amazing Assets menu:
Shape of a volumetric mask. DRM can calculate and render 3D spherical masks of 8 shapes. Each one uses its own calculation algorithm and has different performance cost in the terms of instructions count:
Defines spherical projections count calculated and rendered by one DRM node. Performance cost of the DRM method depends on this value. More masks it calculates, the more expensive it is, and shader becomes slow.
When using DRM inside a shader, take note that various GPU’s have different limitations on the shaders instructions count and Count parameter must be kept as low as possible. While high-end GPU can render hundreds of DRM elements, the same shader may fail to compile on the mobile devices or it may be very slow.
DRM calculation method type:
Simple - Fast mask calculation method. Requires less instructions, but doesn't support Smooth and Noise features.
Advanced - Mask rendering requires more instruction, but supports all visual features.
Chart below displays shader instructions count comparison of Advanced and Simple types:
Just a note, Gradient Noise node from the Shader Graph uses 133 instructions:
DRM uses for loop cycle for calculating mask consisting of multiple objects and Blend Mode defines how results of those iterations are combined:
Additive - Adds the result of the current iteration to the previous. For example, on the image below is demonstrated a mask consisting of two projections. If the Intensity values of those projections are, for example 3 and 4, then the intensity at the intersection zones for the final resultant mask will be 7. Additive blend mode is useful in cases where shader effect depends on the intensity of the resultant mask, for example, in the vertex displacement effects. Depending on the DRM properties (especially Intensity value), output of the DRM node may be in the range of [-∞, +∞]. Always use Saturate or Clamp results of the additive DRM node before using them with the Lerp or similar methods.
Normalized - Inside for loop cycle each mask is smoothly blended with previous one and output of the DRM node always is in the range of [0, 1].
If inside a shader it is necessary to use several identical DRM nodes, but each one with its own properties and use case, then using ID property can be generated alternative variants of the same DRM node.
Defines scope of the DRM properties inside a shader:
Local - DRM properties belong only to a specific material instance and affect only that material or renderer. If scene contains multiple materials using the same DRM node, each material can be updated using a single DRM Controller (in this case DRM properties will be the same for all materials) or each material can be updated separately using its own DRM Controller.
Global - DRM properties are set only once (using DRM Controller) and they are automatically visible to all shaders and materials that reference them. In the example below all scene materials use the same DRM node for rendering Sonar effect and its properties must be the same for all of them, so why update those properties for each material individually, when it is possible to update them just once and all materials will automatically use them:
After choosing DRM settings clicking on the one of 3 shader editor buttons, generates required DRM files and highlights them inside the Project window, that can be drag & dropped inside shader editor or used in HLSL files:
