+//DP_SND_GETSOUNDTIME
+//idea: VorteX
+//darkplaces implementation: VorteX
+//constant definitions:
+float(entity e, float channel) getsoundtime = #533; // get currently sound playing position on entity channel, -1 if not playing or error
+float(string sample) soundlength = #534; // returns length of sound sample in seconds, -1 on error (sound not precached, sound system not initialized etc.)
+//description: provides opportunity to query length of sound samples and realtime tracking of sound playing on entities (similar to DP_GETTIME_CDTRACK)
+//note: beware dedicated server not running sound engine at all, so in dedicated mode this builtins will not work in server progs
+//note also: menu progs not supporting getsoundtime() (will give a warning) since it has no sound playing on entities
+//examples of use:
+// - QC-driven looped sounds
+// - QC events when sound playing is finished
+// - toggleable ambientsounds
+// - subtitles
+
+//DP_VIDEO_DPV
+//idea: LordHavoc
+//darkplaces implementation: LordHavoc
+//console commands:
+// playvideo <videoname> - start playing video
+// stopvideo - stops current video
+//description: indicated that engine support playing videos in DPV format
+
+//DP_VIDEO_SUBTITLES
+//idea: VorteX
+//darkplaces implementation: VorteX
+//cvars:
+// cl_video_subtitles - toggles subtitles showing
+// cl_video_subtitles_lines - how many lines to reserve for subtitles
+// cl_video_subtitles_textsize - font size
+//console commands:
+// playvideo <videoname> <custom_subtitles_file> - start playing video
+// stopvideo - stops current video
+//description: indicates that engine support subtitles on videos
+//subtitles stored in external text files, each video file has it's default subtitles file ( <videoname>.dpsubs )
+//example: for video/act1.dpv default subtitles file will be video/act1.dpsubs
+//also video could be played with custom subtitles file by utilizing second parm of playvideo command
+//syntax of .dpsubs files: each line in .dpsubs file defines 1 subtitle, there are three tokens:
+// <start> <end> "string"
+// start: subtitle start time in seconds
+// end: subtitle time-to-show in seconds, if 0 - subtitle will be showed until next subtitle is started,
+// if below 0 - show until next subtitles minus this number of seconds
+// text: subtitle text, color codes (Q3-style and ^xRGB) are allowed
+//example of subtitle file:
+// 3 0 "Vengeance! Vengeance for my eternity of suffering!"
+// 9 0 "Whelp! As if you knew what eternity was!"
+// 13 0 "Grovel before your true master."
+// 17 0 "Never!"
+// 18 7 "I'll hack you from crotch to gizzard and feed what's left of you to your brides..."
+