buldthensnip/pkg/base/lib_vector.lua
Dany0 a0dd8ea25a Enhanced block building
Much easier to build bridges, bases etc. now. Especially under fire.
2013-01-21 21:23:42 +01:00

373 lines
8.1 KiB
Lua

--[[
This file is part of Ice Lua Components.
Ice Lua Components is free software: you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
Ice Lua Components is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with Ice Lua Components. If not, see <http://www.gnu.org/licenses/>.
]]
function vcross(x1,y1,z1,x2,y2,z2)
return y1*z2 - z1*y2
, z1*x2 - x1*z2
, x1*y2 - y1*x2
end
function vdot(x1,y1,z1,x2,y2,z2)
return x1*x2 + y1*y2 + z1*z2
end
function vlen2(x,y,z)
return x*x + y*y + z*z
end
function vlen(x,y,z)
return math.sqrt(vlen2(x,y,z))
end
function vnorm(x,y,z)
local d = math.max(0.0000001,vlen(x,y,z))
return x/d, y/d, z/d
end
function vrotate(theta,x,y,z,bx,by,bz)
-- glRotate as specified by SGI :D
bx,by,bz = vnorm(bx,by,bz)
-- S = [ 0 -z y ]
-- [ z 0 -x ]
-- [ -y x 0 ]
-- R = uuT + cosO (I - uuT) + sinO S
-- alternatively
-- R = uuT * (1 - cosO) + IcosO + sinO S
local ct = math.cos(theta)
local st = math.sin(theta)
return
x*(bx*bx*(1-ct)+ct) + y*(bx*by*(1-ct) + st*-bz) + z*(bx*bz*(1-ct) + st*by),
x*(by*bx*(1-ct) + st*bz) + y*(by*by*(1-ct)*(1-ct)+ct) + z*(by*bz*(1-ct) + st*-bx),
x*(bz*bx*(1-ct) + st*-by) + y*(bz*by*(1-ct) + st*bx) + z*(bz*bz*(1-ct)+ct)
end
function trace_gap(x,y,z)
local xlen,ylen,zlen
xlen,ylen,zlen = common.map_get_dims()
local l = common.map_pillar_get(math.floor(x), math.floor(z))
i = 1
local h1,h2
h1 = nil
while true do
h2 = l[i+1]
if h2 == ylen-1 then h2 = ylen end
if y < l[i+1] or l[i] == 0 then return h1, h2 end
i = i + l[i]*4
if y < l[i+3] then return h1, h2 end
h1 = l[i+3]
h2 = l[i+1]
end
end
function box_is_clear(x1,y1,z1,x2,y2,z2,canwrap)
local x,z,i
x1 = math.floor(x1)
y1 = math.floor(y1)
z1 = math.floor(z1)
x2 = math.floor(x2)
y2 = math.floor(y2)
z2 = math.floor(z2)
local xlen,ylen,zlen
xlen,ylen,zlen = common.map_get_dims()
if not canwrap then
if x1 < 0 or z1 < 0 then
return false
elseif x2 >= xlen or z2 >= zlen then
return false
end
end
for z=z1,z2 do
for x=x1,x2 do
local l = common.map_pillar_get(x, z)
i = 1
while true do
if l[i+1] == ylen-1 and y2 < ylen then break end
if y2 < l[i+1] then break end
if l[i] == 0 then return false end
i = i + l[i]*4
if y1 < l[i+3] then return false end
end
end
end
return true
end
function trace_map_ray_dist(x1,y1,z1, vx,vy,vz, maxdist, nil_on_maxdist)
if nil_on_maxdist == nil then nil_on_maxdist = true end
local function depsilon(d)
if d < 0.0000001 then
return 0.0000001
else
return d
end
end
local xlen,ylen,zlen
xlen,ylen,zlen = common.map_get_dims()
-- offsets
local fx,fy,fz
if vx < 0 then fx = bx1 else fx = bx2 end
if vy < 0 then fy = by1 else fy = by2 end
if vz < 0 then fz = bz1 else fz = bz2 end
-- direction
local gx,gy,gz
if vx < 0 then gx = -1 else gx = 1 end
if vy < 0 then gy = -1 else gy = 1 end
if vz < 0 then gz = -1 else gz = 1 end
vx = vx * gx
vy = vy * gy
vz = vz * gz
-- cell
local cx,cy,cz
cx = math.floor(x1)
cy = math.floor(y1)
cz = math.floor(z1)
-- subpos
local sx,sy,sz
sx = x1-cx
sy = y1-cy
sz = z1-cz
if gx >= 0 then sx = 1-sx end
if gy >= 0 then sy = 1-sy end
if gz >= 0 then sz = 1-sz end
local dist = 0
local pillar, npillar
npillar = common.map_pillar_get(cx,cz)
pillar = npillar
while true do
local tx = sx/depsilon(vx)
local ty = sy/depsilon(vy)
local tz = sz/depsilon(vz)
local t,d
local ncx,ncy,ncz
ncx,ncy,ncz = cx,cy,cz
if tx < ty and tx < tz then
t = tx
d = 0
ncx = cx + gx
npillar = common.map_pillar_get(ncx,ncz)
elseif ty < tx and ty < tz then
t = ty
d = 1
ncy = cy + gy
else
t = tz
d = 2
ncz = cz + gz
npillar = common.map_pillar_get(ncx,ncz)
end
dist = dist + t
if dist > maxdist and nil_on_maxdist then
return nil, nil, nil, nil, nil, nil, nil
elseif dist > maxdist and not nil_on_maxdist then
return dist, cx, cy, cz, ncx, ncy, ncz
end
local i=1
while true do
if ncy < npillar[i+1] then break end
if npillar[i] == 0 then return dist, cx, cy, cz, ncx, ncy, ncz end
i = i + npillar[i]*4
if ncy < npillar[i+3] then return dist, cx, cy, cz, ncx, ncy, ncz end
end
sx = sx - vx*t
sy = sy - vy*t
sz = sz - vz*t
cx,cy,cz = ncx,ncy,ncz
if d == 0 then sx = 1
elseif d == 1 then sy = 1
else sz = 1 end
pillar = npillar
end
end
function trace_map_box(x1,y1,z1, x2,y2,z2, bx1,by1,bz1, bx2,by2,bz2, canwrap)
local function depsilon(d)
if d < 0.0000001 then
return 0.0000001
else
return d
end
end
-- delta
local dx,dy,dz
dx = x2-x1
dy = y2-y1
dz = z2-z1
-- offsets
local fx,fy,fz
if dx < 0 then fx = bx1 else fx = bx2 end
if dy < 0 then fy = by1 else fy = by2 end
if dz < 0 then fz = bz1 else fz = bz2 end
-- direction
local gx,gy,gz
if dx < 0 then gx = -1 else gx = 1 end
if dy < 0 then gy = -1 else gy = 1 end
if dz < 0 then gz = -1 else gz = 1 end
dx = dx * gx
dy = dy * gy
dz = dz * gz
-- combined box size
local bcx,bcy,bcz
bcx = (bx2-bx1)
bcy = (by2-by1)
bcz = (bz2-bz1)
-- top left offset (note, incorrect name!)
local tlx,tly,tlz
if gx >= 0 then tlx = 0.999 else tlx = 0.001 end
if gy >= 0 then tly = 0.999 else tly = 0.001 end
if gz >= 0 then tlz = 0.999 else tlz = 0.001 end
-- apply offset
x1 = x1 + fx
y1 = y1 + fy
z1 = z1 + fz
bx1 = bx1 - fx
by1 = by1 - fy
bz1 = bz1 - fz
bx2 = bx2 - fx
by2 = by2 - fy
bz2 = bz2 - fz
-- cell
local cx,cy,cz
cx = math.floor(x1)
cy = math.floor(y1)
cz = math.floor(z1)
-- target cell
local tcx,tcy,tcz
tcx = math.floor(x2+fx+gx*0.002)
tcy = math.floor(y2+fy+gy*0.002)
tcz = math.floor(z2+fz+gz*0.002)
-- sub deltas
local sx, sy, sz
sx = (x1 % 1.0) - 0.001
sy = (y1 % 1.0) - 0.001
sz = (z1 % 1.0) - 0.001
if gx >= 0 then sx = 1-sx end
if gy >= 0 then sy = 1-sy end
if gz >= 0 then sz = 1-sz end
-- restricted x/y/z
local rx,ry,rz
rx = nil
ry = nil
rz = nil
-- TODO: unset these when another boundary is crossed
local i
local iend = (
math.abs(tcx-cx)
+ math.abs(tcy-cy)
+ math.abs(tcz-cz)
)
for i=1,iend do
-- get the time it takes to hit the boundary
local tx = sx/depsilon(dx)
local ty = sy/depsilon(dy)
local tz = sz/depsilon(dz)
local t, d, ck
if tx < ty and tx < tz then
-- X first
d = 0
t = tx
elseif ty < tx and ty < tz then
-- Y first
d = 1
t = ty
else
-- Z first
d = 2
t = tz
end
sx = sx - t*dx
sy = sy - t*dy
sz = sz - t*dz
x1 = rx or x1 + t*dx*gx
y1 = ry or y1 + t*dy*gy
z1 = rz or z1 + t*dz*gz
if d == 0 then
-- X first
sx = 1.0
ck = rx or box_is_clear(cx+gx,y1+by1,z1+bz1,cx+gx,y1+by2,z1+bz2,canwrap)
if not ck then rx = cx + tlx end
if not rx then cx = cx + gx end
elseif d == 1 then
-- Y first
sy = 1.0
ck = ry or box_is_clear(x1+bx1,cy+gy,z1+bz1,x1+bx2,cy+gy,z1+bz2,canwrap)
if not ck then ry = cy + tly end
if not ry then cy = cy + gy end
else
-- Z first
sz = 1.0
ck = rz or box_is_clear(x1+bx1,y1+by1,cz+gz,x1+bx2,y1+by2,cz+gz,canwrap)
if not ck then rz = cz + tlz end
if not rz then cz = cz + gz end
end
--if not ck then return x1-bx1, y1-by1, z1-bz1 end
end
--
if rx then rx = rx - fx end
if ry then ry = ry - fy end
if rz then rz = rz - fz end
return rx or x2, ry or y2, rz or z2
end
function isect_line_sphere(x1,y1,z1,fx,fy,fz,x2,y2,z2)
end