SRB2Kart-Saturn/LUASTUFF.md

SRB2Kart Saturn: Custom lua features

mobj.localskin and player.localskin fields

Allow reading and assigning localskins.

mobj.rollsum field

Not netsafe. Returns total sprite rotation value, taking sliptideroll and sloperoll cvars value into account. Mainly for use in visual-only addons like secondcolor.

player.sliproll field

Not netsafe. Returns player's current sliptide roll angle, taking sliptideroll cvar value into account.

hud.setVoteBackground(name)

Changes vote background texture prefix (game looks for PREFIX + "W" or "C" (depends on resolution) + FRAME_NUMBER).

hud.add(fn, "vote") and hud.add(fn, "intermission")

Hud hooks for vote screen and intermission screen. They only get drawer (v) as argument. To check if those hooks are available, check if globals FEATURE_VOTEHUD and FEATURE_INTERMISSIONHUD exist.

x, y = hud.getOffsets(item)

Returns the values of the given HUD item's xoffset/yoffset cvars. Available for any HUD item with offset cvars.

x, y, flags = v.getDrawInfo(item)

Returns the X, Y and flags where the given HUD item will be drawn for the current displayplayer. Available for item, gametypeinfo and minimap.

patch, colormap = v.getColorHudPatch(item)

Returns the patch and colormap to use for the given HUD item. Colorization is based on the user's settings. Available for item and itemmul. Extra arguments for some items:

item

• small: true for small item box, false for big item box.
• dark: true to darken item box. Depends on darkitembox.

itemmul

• small: true for small sticker, false for big sticker.

hudcolor = v.getHudColor()

Returns the displayplayer's HUD color.

colorize = v.useColorHud()

Returns true if colorization is enabled, false otherwise.

v.interpolate(true)

Enables HUD interpolation. Each call to a drawing function will have its coordinates interpolated by assigning an unique ID to every call. For example, three successive calls to v.draw will each have their own ID and interpolation offsets. Pass true to enable interpolation, false to disable.

Alternatively, pass a number to enable interpolation with the specified tag. Tags allow HUD items drawn by the same call to a drawing function to be differentiated. Valid tags range from 0-255. For example, when iterating players, use a unique tag for each player to avoid artifacting:

for p in players.iterate do
	-- enable interpolation, using player numbers as the tag
	-- every draw will have different interp offsets per player
	v.interpolate(#p)

	-- doesn't matter for unconditional draws like this one...
	v.draw(...)

	-- but it does matter if there's a condition!
	-- without tags, this patch would warp between players
	-- whenever their `someVar` changes
	if p.someVar then v.draw(...) end
end

-- don't want interpolation anymore? then disable it
v.interpolate(false)

NOTE: The default tag for true is 0.

v.interpLatch(true)

Enables interpolation offset latching. The next call to a drawing function will have its lerp offsets saved and reused for all following draw calls. Disable with false when done. Interpolation cannot easily "snap" between two points; latching can help overcome this by manually setting the lerp offsets.

v.interpolate(true)

-- X coordinate for the HUD item
-- every so often, this will wrap around to zero
local x = (leveltime*4) % 256

-- draw an interpolated patch, but... when X rolls back to zero,
-- the patch will slide all the way across the screen!
v.draw(x, 100, ...)

-- this is where interpLatch comes into play
-- enable latching, then draw an invisible patch,
-- moving at the same speed as the visible patch
-- the exact coordinates don't matter, it just has to move at the right speed
v.interpLatch(true)
v.draw(leveltime*4, 0, v.cachePatch("K_TRNULL"))

-- now we can draw the patch again, and when X becomes zero,
-- it'll snap right back without sliding across the screen
v.draw(x, 150, ...)

-- don't forget to turn off latching!
v.interpLatch(false)

When using a custom string drawer, enable this mode to avoid interpolation artifacting when the string changes.

mobj.spritexscale, mobj.spriteyscale, mobj.spritexoffset, mobj.spriteyoffset, mobj.rollangle, mobj.sloperoll, mobj.rollmodel fields

Same fields as in SRB2 2.2

S_StopSoundByNum

Allows stopping specific sound globally. Because this function starts with S_, like state, checking if it exists is a bit more complicated:

if rawget(_G, "S_StopSoundByNum") ~= nil then
    ... -- Can use it
end