Instead of using these expressions, adding "lib" in fron of static libs is now done via CMAKE_STATIC_LIBRARY_PREFIX when building static libs on Windows.
WebGL doesn't follow the OpenGL standard format for the glGetString(GL_SHADING_LANGUAGE_VERSION) return value. Chrome for example will return "OpenGL ES GLSL ES 3.00 (WebGL GLSL ES 3.00 (OpenGL ES GLSL ES 3.0 Chromium))", which does not start with the version number as the standard suggests.
This fix will simply cut off any text preceding the first digit found in the string, if any.
Consolidated audio processing code into the PCM class, removing the BeatDetect class in the process. Beat detection now uses the same algorithm as Milkdrop, passing the proper relative bass/mid/treb values to presets. Makes many presets look less jumpy/flickering, as the values are now (smoothly) alternating around 1.0.
Updating frame audio is now done in a function that must specifically be called. Any subsequent calls to GetFrameAudioData() will then return the exact same copy of the audio data. As of now with the exception that new waveform data may be passed in via a separate thread, which will then be returned and might not match the spectrum data. Will fix that in a later commit.
Removed the previous FFT algorithm, now using a modernized version of the original Milkdrop FFT transform which also has both an equalizer and frequency envelope, making it slightly more sophisticated.
Modernization mainly included replacing raw pointer arrays with std::vector and using STL types/functions for the calculation, specifically std::complex as the FFT heavily uses these numbers. This makes the code more compact and readable.
Manually tested both original and modernized versions of the class to test if the algorithm still returns the exact same results, which is the case.
Now we don't add the half texel offset to the vertex coordinates, but to the calculated u/v, which will prevent the texture wrapping (happens mostly with "nearest" interpolation lookups) mentioned in Milkdrop's code from happening, but make the mesh exactly fill the screen.
This avoids two fullscreen draw calls during transitions, and should also be slightly faster than using glBlitFramebuffer().
As with all drawing operations, we currently don't really care about the target framebuffer size or aspect ratio and just draw a quad over the whole viewport.
This makes hard transitions a bit "smoother", as they won't always start from a black screen. Not really noticeable with fast presets, but some slow-warping ones will now gently dissolve the previous image.
Also cleaned up the code a bit, the version string format is well-defined by the standard - we just have to cut off anything after the space if there is any.
Use the same basic logic as Milkdrop. Also automatically declare a shorthand "texsize_randXX" uniform for prefixed random texture names as preset authors expect.
Only GLES 3.2 supports glColorMaski, which would exclude any platforms only supporting GLES 3.0 or 3.1, so we simply change the color attachment accordingly. This change also improves VRAM usage, as now there's only a single u/v texture used for both framebuffers as required.
