From f85a54a07046fea181b7c007f6b1379b8cd6d279 Mon Sep 17 00:00:00 2001 From: HybridDog Date: Thu, 27 Aug 2015 20:44:45 +0200 Subject: [PATCH] :cat2: --- init.lua | 90 +++++++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 89 insertions(+), 1 deletion(-) diff --git a/init.lua b/init.lua index fbbc211..4924f0f 100644 --- a/init.lua +++ b/init.lua @@ -316,7 +316,7 @@ function funcs.straightdelay(s, v, a) return (math.sqrt(v*v+2*a*s)-v)/a end -vector.zero = {x=0, y=0, z=0} +vector.zero = vector.new() function funcs.sun_dir(time) if not time then @@ -367,6 +367,10 @@ function funcs.move(p1, p2, s) ) end +function funcs.from_number(i) + return {x=i, y=i, z=i} +end + local explosion_tables = {} function funcs.explosion_table(r) local table = explosion_tables[r] @@ -399,6 +403,90 @@ function funcs.explosion_table(r) return tab end +local default_nparams = { + offset = 0, + scale = 1, + seed = 1337, + octaves = 6, + persist = 0.6 +} +function funcs.explosion_perlin(pos, rmin, rmax, nparams) + local t1 = os.clock() + + local r = math.ceil(rmax) + nparams = nparams or {} + for i,v in pairs(default_nparams) do + nparams[i] = nparams[i] or v + end + nparams.spread = nparams.spread or vector.from_number(r*5) + + local map = minetest.get_perlin_map(nparams, vector.from_number(r+r+1)):get3dMap_flat(pos) + + local id = 1 + + + local bare_maxdist = rmax*rmax + local bare_mindist = rmin*rmin + + local maxdist = math.sqrt(bare_maxdist) + local mindist = math.sqrt(bare_mindist) + local dist_diff = maxdist-mindist + mindist = mindist/dist_diff + + local pval_min, pval_max + + local tab, n = {}, 1 + for z=-r,r do + local bare_dist = z*z + for y=-r,r do + local bare_dist = bare_dist+y*y + for x=-r,r do + local bare_dist = bare_dist+x*x + local add = bare_dist < bare_mindist + local pval, distdiv + if not add + and bare_dist <= bare_maxdist then + distdiv = math.sqrt(bare_dist)/dist_diff-mindist + pval = math.abs(map[id]) -- strange perlin values… + if not pval_min then + pval_min = pval + pval_max = pval + else + pval_min = math.min(pval, pval_min) + pval_max = math.max(pval, pval_max) + end + add = true--distdiv < 1-math.abs(map[id]) + end + + if add then + local np={x=x, y=y, z=z} + tab[n] = {np, pval, distdiv} + n = n+1 + end + id = id+1 + end + end + end + + -- change strange values + local pval_diff = pval_max - pval_min + pval_min = pval_min/pval_diff + + for n,i in pairs(tab) do + if i[2] then + local new_pval = (i[2]/pval_diff - pval_min) + if i[3] < math.abs(new_pval) then + tab[n] = {i[1]} + else + tab[n] = nil + end + end + end + + minetest.log("info", string.format("[vector_extras] table created after ca. %.2fs", os.clock() - t1)) + return tab +end + local circle_tables = {} function funcs.circle(r) local table = circle_tables[r]