Fluids entering iron tanks use fallback texture when flowing texture is missing (#53)

* Fluids entering iron tanks will use still texture when flowing texture is missing

* Code style fixes.

Author: asoftbird

src/main/java/mods/railcraft/client/render/FluidRenderer.java

@@ -49,8 +49,13 @@ public static ResourceLocation getFluidSheet(Fluid fluid) {
 
     public static ResourceLocation setupFlowingLiquidTexture(Fluid fluid, IIcon[] texArray) {
         if (fluid == null) return null;
-        IIcon top = RenderTools.getSafeIcon(fluid.getStillIcon());
+
         IIcon side = RenderTools.getSafeIcon(fluid.getFlowingIcon());
+        if ((fluid.getStillIcon() != null) && (fluid.getFlowingIcon() == null)) {
+            side = RenderTools.getSafeIcon(fluid.getStillIcon());
+        }
+
+        IIcon top = RenderTools.getSafeIcon(fluid.getStillIcon());
         texArray[0] = top;
         texArray[1] = top;
         texArray[2] = side;