The Initial Modules appear to be clamped to a zero to 1 time frame since 4.8 was released. Projects that are converted from 4.7.6 will have correctly working particle systems, but adding a new particle system of the same makeup will force the new system to use a clamped range.

[Image Removed]

Left is created in 4.9.1, Right is created in 4.7.6 and project converted to 4.9.1

Attached 4.7.6, 4.8.3 and 4.9.1 project for clarity. 4.7.6 shows expected and working behavior, 4.8.3 and 4.9.3 show new particle systems not functioning but converted particle system still functioning.

Steps to Reproduce
  1. Create a New Blank Project with No Starter Content
  2. Create a Translucency Unlit Material will Particle Color plugged into Emissive COlor and Opacity
  3. Create a New Particle System
  4. Assign the created Material to the New Particle System
  5. Remove the Color over Life Module
  6. Add an Initial COlor MOdule with the following settings:
    -Constant Curve, pt#1 In 0, Out (1,0,0), pt#2 In 2, Out (0,1,0)
  7. Set the Initial Size Module to the following settings:
    -Constant Curve, pt#1 In 0, Out (25,25,25), pt#2 Out (0,0,0)
  8. In the Required MOdule, set the Emitter Duration to 2

RESULTS: Same as on left of picture above

EXPECTED: Same as right of picture above

**Quick Reproduction, open attached 483 or 491 projects**

Have Comments or More Details?

Head over to the existing Questions & Answers thread and let us know what's up.

Login to Vote

ComponentUE - Graphics Features
Affects Versions4.
CreatedSep 18, 2015
ResolvedNov 23, 2015
UpdatedJul 14, 2021
View Jira Issue