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Remove unused vector.triangle code and try to make it a bit faster

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This commit is contained in:
HybridDog 2020-03-27 18:30:19 +01:00
parent f7dbb1a884
commit 275ec4af3b
1 changed files with 13 additions and 53 deletions
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66
init.lua
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@ -1023,63 +1023,18 @@ function funcs.triangle(pos1, pos2, pos3)
z = {"y", "x"},
}
local other_dirs = all_other_dirs[dir]
-- Sort the positions along the other directions
--[[
local sorteds = {}
for i = 1,2 do
local odir = other_dirs[i]
local ps = {}
if pos1[odir] < pos2[odir] then
if pos1[odir] < pos3[odir] then
ps[1] = pos1
if pos2[odir] < pos3[odir] then
ps[2] = pos2
ps[3] = pos3
else
ps[3] = pos2
ps[2] = pos3
end
else
ps[1] = pos3
ps[2] = pos1
ps[3] = pos2
end
elseif pos1[odir] < pos3[odir] then
ps[1] = pos2
ps[2] = pos1
ps[3] = pos3
else
ps[3] = pos1
if pos2[odir] < pos3[odir] then
ps[1] = pos2
ps[2] = pos3
else
ps[1] = pos3
ps[2] = pos2
end
end
sorteds[i] = ps
end
--~ p1[i] = sorteds[odir][1][odir]
--~ p2[i] = sorteds[odir][3][odir]
--]]
-- The boundaries of the 2D AABB along other_dirs
local odir1, odir2 = other_dirs[1], other_dirs[2]
local pos1_2d = {pos1[odir1], pos1[odir2]}
local pos2_2d = {pos2[odir1], pos2[odir2]}
local pos3_2d = {pos3[odir1], pos3[odir2]}
-- The boundaries of the 2D AABB along other_dirs
local p1 = {}
local p2 = {}
for i = 1,2 do
p1[i] = math.floor(math.min(pos1_2d[i], pos2_2d[i], pos3_2d[i]))
p2[i] = math.ceil(math.max(pos1_2d[i], pos2_2d[i], pos3_2d[i]))
end
-- The lines along the triangle boundaries
--~ local lines = {}
--~ local ps2 = sorteds[2]
--~ local s = {ps2[1][other_dirs[1]], ps2[1][other_dirs[2]]}
--~ local e = {ps2[2][other_dirs[1]], ps2[2][other_dirs[2]]}
--~ local line_left = {s[1], s[2], e[1] - s[1], e[2] - s[2]}
-- https://www.scratchapixel.com/lessons/3d-basic-rendering/rasterization-practical-implementation/rasterization-stage
local function edgefunc(p1, p2, pos)
@ -1087,25 +1042,30 @@ function funcs.triangle(pos1, pos2, pos3)
- (pos[2] - p1[2]) * (p2[1] - p1[1])
end
local a_all_inv = 1.0 / edgefunc(pos1_2d, pos2_2d, pos3_2d)
local step_k3 = - (pos2_2d[1] - pos1_2d[1]) * a_all_inv
local step_k1 = - (pos3_2d[1] - pos2_2d[1]) * a_all_inv
-- Calculate the triangle points
local points = {}
local barycentric_coords = {}
local n = 0
-- It is possible to further optimize this
for v1 = p1[1], p2[1] do
for v2 = p1[2], p2[2] do
-- Not optimized
local p = {v1, v2}
local k3 = edgefunc(pos1_2d, pos2_2d, p) * a_all_inv
local k1 = edgefunc(pos2_2d, pos3_2d, p) * a_all_inv
local p = {v1, p1[2]}
local k3 = edgefunc(pos1_2d, pos2_2d, p) * a_all_inv
local k1 = edgefunc(pos2_2d, pos3_2d, p) * a_all_inv
for _ = p1[2], p2[2] do
local k2 = 1 - k1 - k3
if k1 >= 0 and k2 >= 0 and k3 >= 0 then
-- On triangle
local h = math.floor(k1 * pos1[dir] + k2 * pos2[dir] +
k3 * pos3[dir] + 0.5)
n = n+1
points[n] = {[odir1] = v1, [odir2] = v2, [dir] = h}
points[n] = {[odir1] = v1, [odir2] = p[2], [dir] = h}
barycentric_coords[n] = {k1, k2, k3}
end
p[2] = p[2]+1
k3 = k3 + step_k3
k1 = k1 + step_k1
end
end
return points, n, barycentric_coords