Update TODO

TODO.md

@@ -1,4 +1,13 @@
 # TODO
+- [ ] Account for the fact that a larger minor axis "hardens" splat edges
+    - Maybe shift the alpha gradient, or incorporate into shader
+- [ ] Rework SplatBinder system to collect all splat objects in the scene and
+      combine their buffers
+- [ ] Write shader to calculate Gaussians at runtime
+    - Texture lookups are slow on mobile
+- [ ] ~~Write shader that prevents pixel overdraw~~
+    - ~~Applies cumulative alpha,while drawing back to front, and writes to the
+      Z-buffer after a certain threshold~~
 - [ ] Optimize CalculateAxes.hlsl
 - [ ] Allow splat data buffers to be accessible by other VFX Graphs
 - [ ] Support SOGS format
@@ -12,4 +21,7 @@
 - [x] Rewrite SH Array to use interleaved RGB rather than contiguous data per 
       channel
 - [x] Switch to using ByteAddressBuffers instead of loops in CalculateSH.hlsl
-    - Used StructuredBuffer\<float3\> instead
+    - Used StructuredBuffer\<float3\> instead
+
+# NOTES
+- Does VFX Graph calculate the Update and Render blocks before applying Z-test?