Showview

showview <x> <y> <z> <angle> <horiz> <sector> <scrn_x1> <scrn_y1> <scrn_x2> <scrn_y2>

Displays on-screen the view from in-game coordinates (<x>,<y>,<z>), looking at angle <angle> and with z-angle (up and down) <horiz>, between screen coordinates (<scrn_x1>,<scrn_y1>) and (<scrn_x2>,<scrn_y2>).

<sector> is the sector that contains the in-game coordinates.

The on-screen coordinates can be in any shape; they do not have to be in the same x-y ratio as the screen resolution. However, different ratios can result in warping or graphical glitches in the view. The on-screen coordinates are in 320×200 scale.

Keep in mind when using this command that the game will have to completely redraw everything from the specified perspective, which can produce a sizeable framerate hit.

This example will embed a small version of the player's view near the top left corner of the screen:

getplayer[THISACTOR].posx x
getplayer[THISACTOR].posy y
getplayer[THISACTOR].posz z
getplayer[THISACTOR].angle ang
getplayer[THISACTOR].horiz horiz
getplayer[THISACTOR].horizoff temp
addvarvar horiz temp
updatesectorz x y z sect
showview x y z ang horiz sect 16 8 56 39

This lengthy example will create a "gun camera" that shows a closeup view of wherever the player is currently aiming. In addition to showview and basic EDuke commands, it also uses updatesectorz, myos, and hitscan, as well as the event EVENT_DISPLAYREST.

gamevar sv_scrnx1 0 0
gamevar sv_scrny1 0 0
gamevar sv_scrnx2 0 0
gamevar sv_scrny2 0 0
gamevar sv_sect 0 0
gamevar sv_temp1 0 0
gamevar sv_temp2 0 0
gamevar sv_x 0 0
gamevar sv_y 0 0
gamevar sv_z 0 0
gamevar sv_hitx 0 0
gamevar sv_hity 0 0
gamevar sv_hitz 0 0
gamevar sv_cos 0 0
gamevar sv_sin 0 0
gamevar sv_ang 0 0
gamevar sv_horiz 0 0

state sv_playerview
  getplayer[THISACTOR].posx sv_x
  getplayer[THISACTOR].posy sv_y
  getplayer[THISACTOR].posz sv_z
  subvar sv_z 512
  getplayer[THISACTOR].cursectnum sv_sect
ends

onevent EVENT_DISPLAYREST {
// get coords
  setvar sv_scrnx1 23
  setvar sv_scrny1 16
  setvarvar sv_scrnx2 sv_scrnx1 addvar sv_scrnx2 50
  setvarvar sv_scrny2 sv_scrny1 addvar sv_scrny2 47 //  31 for correct ratio
// display frame
  setvarvar sv_temp1 sv_scrnx1 subvar sv_temp1 7
  setvarvar sv_temp2 sv_scrny1 subvar sv_temp2 8
  myos sv_temp1 sv_temp2 SCREENBREAK6 0 16
// do the hitscan
  getplayer[THISACTOR].ang sv_ang
  getplayer[THISACTOR].horiz sv_horiz
  getplayer[THISACTOR].posx sv_hitx
  getplayer[THISACTOR].posy sv_hity
  getplayer[THISACTOR].posz sv_hitz
  getplayer[THISACTOR].cursectnum sv_temp2
  subvar sv_hitz 512
  cos sv_cos sv_ang
  sin sv_sin sv_ang
  setvar sv_temp1 100
  subvarvar sv_temp1 sv_horiz
  getplayer[THISACTOR].horizoff sv_horiz
  subvarvar sv_temp1 sv_horiz
  shiftvarl sv_temp1 11
  hitscan sv_hitx sv_hity sv_hitz sv_temp2 sv_cos sv_sin sv_temp1 sv_temp2 sv_temp1 sv_temp1 sv_hitx sv_hity sv_hitz CLIPMASK1

  getplayer[THISACTOR].horiz sv_temp1
  getplayer[THISACTOR].horizoff sv_horiz
  addvarvar sv_horiz sv_temp1

// get distance between player and hitscan location
  getplayer[THISACTOR].posx sv_x
  getplayer[THISACTOR].posy sv_y
  getplayer[THISACTOR].posz sv_z
  subvarvar sv_x sv_hitx
  mulvarvar sv_x sv_x
  subvarvar sv_y sv_hity
  mulvarvar sv_y sv_y
  addvarvar sv_x sv_y
  sqrt sv_x sv_x

  ifvarl sv_x 768 state sv_playerview // if dist < 768, just show the player's view
  else { // otherwise, move camera 768 units back from hitscan location on x-y plane and adjust z accordingly
	subvarvar sv_z sv_hitz
	mulvar sv_z 768
	ifvare sv_x 0 setvar sv_x 1
	divvarvar sv_z sv_x
	addvarvar sv_z sv_hitz
	setvarvar sv_x sv_hitx
	setvarvar sv_y sv_hity
	mulvar sv_cos -768
	mulvar sv_sin -768
	divvar sv_cos 16384
	divvar sv_sin 16384
	addvarvar sv_x sv_cos
	addvarvar sv_y sv_sin
	subvar sv_z 512
// if the calculated position isn't in a sector (this does happen) then just show the player's view
	updatesectorz sv_x sv_y sv_z sv_sect
	ifvare sv_sect -1 state sv_playerview
// make sure the camera can still see the hitscan location
	cansee sv_x sv_y sv_z sv_sect sv_hitx sv_hity sv_hitz sv_temp2 sv_temp1
	ifvare sv_temp1 0 state sv_playerview
  }
// check again to make sure we're in a sector
  ifvarn sv_sect -1 {
	// x y z ang horiz sect scrn_x scrn_y scrn_x2 scrn_y2
	showview sv_x sv_y sv_z sv_ang sv_horiz sv_sect sv_scrnx1 sv_scrny1 sv_scrnx2 sv_scrny2
  }
// display crosshair
  addvarvar sv_scrnx1 sv_scrnx2 divvar sv_scrnx1 2
  addvarvar sv_scrny1 sv_scrny2 divvar sv_scrny1 2
  myos sv_scrnx1 sv_scrny1 CROSSHAIR 0 0
}
endevent