libprojectM Release 4.1.6

This release fixes one issue from the previous 4.1.5 release which prevents building libprojectM on Windows when using boost::filesystem. In addition to this build fix, numerous preset rendering quality improvements were added.

Huge thanks to @yoyofr for all the testing and fixing these issues!

What's Changed

• Fix compilation issue with boost::filesystem caused by a missing #include statement.
• Blur textures now use the correct source image (previous frame instead of warped image).
• A vertex shader uniform wasn't set and used uninitialized, causing custom waveforms in "dot" mode to not display properly or at all.
• Fixed some math errors in the default waveform calculations, like placing waveforms at the opposite Y coordinate.
• Fixed the decay value in presets being clamped to a max value of 0.9375 instead of 1.0, causing most Milkdrop 1.4 presets to be rendered way too dark.
• Fixed sep parameter in custom waveforms using the wrong number of samples.
• Added additional row-access function overloads for matrices in HLSL/GLSL transpiler.
• Removed half-texel offset in warp shaders, which wasn't required in OpenGL. This fixes an unintended left-top "drift" in all presets.
• Added missing fwidth intrinsic function in HLSL/GLSL transpiler.
• Changed an integer constant to float in the custom acos(float) function implementation in the HLSL/GLSL transpiler, fixing a shader compilation error.
• Fixed erroneous type casting in PCM smoothing logic in custom waves.
• Added a special case for pow(x, 1) in the HLSL/GLSL transpiler, replacing it with a literal x to match DirectX/HLSL behavior in cases x is negative.
• Fixed an issue with loaded presets losing their textures if the application changed texture paths between frames.
• Added more GitHub Actions workflow combinations to check additional build parameters.
• Put the PS() function in its own line in the HLSL/GLSL transpiler for better readability in case of shader compilation failures.

Full Changelog: v4.1.5...v4.1.6