Various Optimisation to Free-slip Hydraulic Erosion

Release 0.3.0-Preview.3

Optimisation to free-slip hydraulic erosion (#1)

• Heightmap is now precached into shared memory before normal map calculation for reduced memory latency when the same pixel is accessed upto 9 times.
• Caching from global to shared memory is now done in parallel to utilise as many threads as possible. Improvement to exisiting caching algorithm to make it smarter such that it can determine if the number of thread in a block is sufficient to cache all data in parallel, and reuse threads whenever necessary.
• Adding checker whenever loadChunksAsync() is called and only proceed when there is at least one chunk is not loaded or rendering buffer needs be updated, this avoids unecessary calls to map rendering buffer and chunk checking.
• Removing FP32 normalmap storage, integrating normalmap and heightmap into one rendering buffer, RGB channel being normalmap and A channel being heightmap. Cut down the number of kernel launch and memory copy both by around 20%.
• Integrating FP32-INT16 converter into normalmap generator, and renamed into generateRenderingBufferKERNEL().
• No longer generate and use global-local index and interpolation table when free-slip hydraulic erosion is disabled.

General fixes and improvement

• Fixing syntax error from compiler related to built-in threadpool when emplace_void() function is called.
• Changing new to make_unique for better practice.
• Cut down rendering buffer clear buffer size by 20%.
• Update to address changes in dependencies.
• Fixing incorrect serialisation size.
• Remove some redundant codes.