* split up FMultiPatchTexture into a builder class and the actual image source.
* since images can now be referenced by multiple textures the old redirection mechanism has been removed. It can be done better and less intrusive now. Simple single patch textures already directly reference the underlying patch image now.
* allocate all image source related data from a memory arena. Since this is all static this makes it a lot easier to free this in bulk.
This class has only meaning for software-based warping so it doesn't have to be a part of the FTexture hierarchy.
Making it a subclass of FSoftwareTexture is fully sufficient.
A section is a continuous part of a sector or in some case of several nearby continuous parts. For sectors with far away parts multiple sections will be created, especially when they lie in disjoint parts of the map.
This is mainly supposed to cut down on time for linking dynamic lights. Since they need to traverse subsectors to find all touching sidedefs a more coarse data structure that only contains the info needed for this is more suitable. In particular, this does not contain any intra-sector lines, i.e. those with both sides in the same sector.
The original idea was to let Vulkan do this completely differently, but if that comes to pass it should be done without having generic data maintenance code on the API side.
Added full-panning stereo, improvement of channel management, and many other things.
Also, I have implemented an ability to use custom WOPL (for libADLMIDI) and WOPN (for libOPNMIDI) banks from the same path as "soundfonts", but also, in the same environment, the "fm_banks" folder was added for WOPL/WOPN storing purposes.
To toggle usage of embedded or custom bank, I have added togglable booleans. When bank fails to be loaded, the default embedded bank is getting to be used as fallback.
ADLMIDI 1.4.0 2018-10-01
* Implemented a full support for Portamento! (Thanks to [Jean Pierre Cimalando](https://github.com/jpcima) for a work!)
* Added support for SysEx event handling! (Thanks to [Jean Pierre Cimalando](https://github.com/jpcima) for a work!)
* Added support for GS way of custom drum channels (through SysEx events)
* Ignore some NRPN events and lsb bank number when using GS standard (after catching of GS Reset SysEx call)
* Added support for CC66-Sostenuto controller (Pedal hold of currently-pressed notes only while CC64 holds also all next notes)
* Added support for CC67-SoftPedal controller (SoftPedal lowers the volume of notes played)
* Fixed correctness of CMF files playing
* Fixed unnecessary overuse of chip channels by blank notes
* Added API to disable specific MIDI tracks or play one of MIDI tracks solo
* Added support for more complex loop (loopStart=XX, loopEnd=0). Where XX - count of loops, or 0 - infinite. Nested loops are supported without of any limits.
* Added working implementation of TMB's velocity offset
* Added support for full-panning stereo option (Thanks to [Christopher Snowhill](https://github.com/kode54) for a work!)
* Fixed inability to play high notes due physical tone frequency out of range on the OPL3 chip
OPNMIDI 1.4.0 2018-10-01
* Implemented a full support for Portamento! (Thanks to [Jean Pierre Cimalando](https://github.com/jpcima) for a work!)
* Added support for SysEx event handling! (Thanks to [Jean Pierre Cimalando](https://github.com/jpcima) for a work!)
* Added support for GS way of custom drum channels (through SysEx events)
* Ignore some NRPN events and lsb bank number when using GS standard (after catching of GS Reset SysEx call)
* Added support for CC66-Sostenuto controller (Pedal hold of currently-pressed notes only while CC64 holds also all next notes)
* Added support for CC67-SoftPedal controller (SoftPedal lowers the volume of notes played)
* Resolved a trouble which sometimes makes a junk noise sound and unnecessary overuse of chip channels
* Volume models support taken from libADLMIDI has been adapted to OPN2's chip speficis
* Fixed inability to play high notes due physical tone frequency out of range on the OPN2 chip
* Added support for full-panning stereo option
ADL&OPN Hotfix: re-calculated default banks
The fix on side of measurer of OPL3-BE and OPN2-BE where some instruments getting zero releasing time.
