| | |
| | | end |
| | | |
| | | |
| | | -- Based on code by Uberi: https://gist.github.com/Uberi/3125280 |
| | | --- Iterates over the node positions along the specified ray. |
| | | -- The returned positions will not include the starting position. |
| | | function technic.trace_node_ray(pos, dir, range) |
| | | local p = vector.round(pos) |
| | | local x_step, y_step, z_step = 0, 0, 0 |
| | | local x_component, y_component, z_component = 0, 0, 0 |
| | | local x_intersect, y_intersect, z_intersect = 0, 0, 0 |
| | | local x_step = dir.x > 0 and 1 or -1 |
| | | local y_step = dir.y > 0 and 1 or -1 |
| | | local z_step = dir.z > 0 and 1 or -1 |
| | | |
| | | if dir.x == 0 then |
| | | x_intersect = math.huge |
| | | elseif dir.x > 0 then |
| | | x_step = 1 |
| | | x_component = 1 / dir.x |
| | | x_intersect = x_component |
| | | else |
| | | x_step = -1 |
| | | x_component = 1 / -dir.x |
| | | end |
| | | if dir.y == 0 then |
| | | y_intersect = math.huge |
| | | elseif dir.y > 0 then |
| | | y_step = 1 |
| | | y_component = 1 / dir.y |
| | | y_intersect = y_component |
| | | else |
| | | y_step = -1 |
| | | y_component = 1 / -dir.y |
| | | end |
| | | if dir.z == 0 then |
| | | z_intersect = math.huge |
| | | elseif dir.z > 0 then |
| | | z_step = 1 |
| | | z_component = 1 / dir.z |
| | | z_intersect = z_component |
| | | else |
| | | z_step = -1 |
| | | z_component = 1 / -dir.z |
| | | end |
| | | local i = 1 |
| | | return function(p) |
| | | -- Approximation of where we should be if we weren't rounding |
| | | -- to nodes. This moves forward a bit faster then we do. |
| | | -- A correction is done below. |
| | | local real_x = pos.x + (dir.x * i) |
| | | local real_y = pos.y + (dir.y * i) |
| | | local real_z = pos.z + (dir.z * i) |
| | | |
| | | return function() |
| | | if x_intersect < y_intersect then |
| | | if x_intersect < z_intersect then |
| | | -- How far off we've gotten from where we should be. |
| | | local dx = math.abs(real_x - p.x) |
| | | local dy = math.abs(real_y - p.y) |
| | | local dz = math.abs(real_z - p.z) |
| | | |
| | | -- If the real position moves ahead too fast, stop it so we |
| | | -- can catch up. If it gets too far ahead it will smooth |
| | | -- out our movement too much and we won't turn fast enough. |
| | | if dx + dy + dz < 2 then |
| | | i = i + 1 |
| | | end |
| | | |
| | | -- Step in whichever direction we're most off course in. |
| | | if dx > dy then |
| | | if dx > dz then |
| | | p.x = p.x + x_step |
| | | x_intersect = x_intersect + x_component |
| | | else |
| | | p.z = p.z + z_step |
| | | z_intersect = z_intersect + z_component |
| | | end |
| | | elseif y_intersect < z_intersect then |
| | | elseif dy > dz then |
| | | p.y = p.y + y_step |
| | | y_intersect = y_intersect + y_component |
| | | else |
| | | p.z = p.z + z_step |
| | | z_intersect = z_intersect + z_component |
| | | end |
| | | if vector.distance(pos, p) > range then |
| | | return nil |
| | | end |
| | | return p |
| | | end |
| | | end, vector.round(pos) |
| | | end |
| | | |
| | | |
| | | --- Like trace_node_ray, but includes extra positions close to the ray. |
| | | function technic.trace_node_ray_fat(pos, dir, range) |
| | | local x_step = dir.x > 0 and 1 or -1 |
| | | local y_step = dir.y > 0 and 1 or -1 |
| | | local z_step = dir.z > 0 and 1 or -1 |
| | | |
| | | local next_poses = {} |
| | | |
| | | local i = 1 |
| | | return function(p) |
| | | local ni, np = next(next_poses) |
| | | if np then |
| | | next_poses[ni] = nil |
| | | return np |
| | | end |
| | | |
| | | -- Approximation of where we should be if we weren't rounding |
| | | -- to nodes. This moves forward a bit faster then we do. |
| | | -- A correction is done below. |
| | | local real_x = pos.x + (dir.x * i) |
| | | local real_y = pos.y + (dir.y * i) |
| | | local real_z = pos.z + (dir.z * i) |
| | | |
| | | -- How far off we've gotten from where we should be. |
| | | local dx = math.abs(real_x - p.x) |
| | | local dy = math.abs(real_y - p.y) |
| | | local dz = math.abs(real_z - p.z) |
| | | |
| | | -- If the real position moves ahead too fast, stop it so we |
| | | -- can catch up. If it gets too far ahead it will smooth |
| | | -- out our movement too much and we won't turn fast enough. |
| | | if dx + dy + dz < 2 then |
| | | i = i + 1 |
| | | end |
| | | |
| | | -- Step in whichever direction we're most off course in. |
| | | local sx, sy, sz -- Whether we've already stepped along each axis |
| | | if dx > dy then |
| | | if dx > dz then |
| | | sx = true |
| | | p.x = p.x + x_step |
| | | else |
| | | sz = true |
| | | p.z = p.z + z_step |
| | | end |
| | | elseif dy > dz then |
| | | sy = true |
| | | p.y = p.y + y_step |
| | | else |
| | | sz = true |
| | | p.z = p.z + z_step |
| | | end |
| | | |
| | | if vector.distance(pos, p) > range then |
| | | return nil |
| | | end |
| | | |
| | | -- Add other positions that we're significantly off on. |
| | | -- We can just use fixed integer keys here because the |
| | | -- table will be completely cleared before we reach this |
| | | -- code block again. |
| | | local dlen = math.sqrt(dx*dx + dy*dy + dz*dz) |
| | | -- Normalized axis deltas |
| | | local dxn, dyn, dzn = dx / dlen, dy / dlen, dz / dlen |
| | | if not sx and dxn > 0.5 then |
| | | next_poses[1] = vector.new(p.x + x_step, p.y, p.z) |
| | | end |
| | | if not sy and dyn > 0.5 then |
| | | next_poses[2] = vector.new(p.x, p.y + y_step, p.z) |
| | | end |
| | | if not sz and dzn > 0.5 then |
| | | next_poses[3] = vector.new(p.x, p.y, p.z + z_step) |
| | | end |
| | | |
| | | return p |
| | | end, vector.round(pos) |
| | | end |
| | | |