clang: unsigned>0 checks

Engine/source/T3D/fx/particleEmitter.h

@@ -87,7 +87,7 @@ class ParticleEmitterData : public GameBaseData
    /// of the ambient color on the particle.
    F32 ambientFactor;
 
-   U32   lifetimeMS;                         ///< Lifetime of particles
+   S32   lifetimeMS;                         ///< Lifetime of particles
    U32   lifetimeVarianceMS;                 ///< Varience in lifetime from 0 to n
 
    bool  overrideAdvance;                    ///<

Engine/source/T3D/fx/ribbon.cpp

@@ -354,7 +354,7 @@ void Ribbon::addSegmentPoint(Point3F &point, MatrixF &mat) {
    U32 segmentsToDelete = checkRibbonDistance(mDataBlock->segmentsPerUpdate);
 
    for (U32 i = 0; i < segmentsToDelete; i++) {
-      U32 last = mSegmentPoints.size() - 1;
+      S32 last = mSegmentPoints.size() - 1;
       if (last < 0)
          break;
       mTravelledDistance += last ? (mSegmentPoints[last] - mSegmentPoints[last-1]).len() : 0;