Fallen graphics

Integrate rexarcorum's new particle images for Fallen

game/modules/tome/data/gfx/particles/blood_trail.lua

+-- ToME - Tales of Maj'Eyal
+-- Copyright (C) 2009 - 2019 Nicolas Casalini
+--
+-- This program is free software: you can redistribute it and/or modify
+-- it under the terms of the GNU General Public License as published by
+-- the Free Software Foundation, either version 3 of the License, or
+-- (at your option) any later version.
+--
+-- This program 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 General Public License for more details.
+--
+-- You should have received a copy of the GNU General Public License
+-- along with this program.  If not, see <http://www.gnu.org/licenses/>.
+--
+-- Nicolas Casalini "DarkGod"
+-- darkgod@te4.org
+
+-- Make the 2 main forks
+
+local sizeratio = 64 / engine.Map.tile_w
+
+local dir = dir
+local dist = (range or 1) * engine.Map.tile_w
+
+local life = 32
+local points = {}
+points[#points+1] = {size=4, x=0, y=0, prev=-1, angle=0, vel=0}
+for i = 1, 16 do
+	local x = rng.range(-2, 2) / sizeratio
+	local y = -dist / 16 * i
+	-- local si = math.sqrt(i) * 0.8
+	local size
+	if i <= 4 then size = 16 - i * 3
+	else size = points[#points].size * 0.92
+	end
+	points[#points+1] = {angle=-math.pi/2, vel=y/life/sizeratio * ((grab and 1) or -1), size=(i==16) and 1 or size, x=x, y=y, prev=#points-1}
+end
+local nbp = #points
+
+return { engine=core.particles.ENGINE_LINES, system_rotation=dir, generator = function()
+	local p = table.remove(points, 1)
+	if not p then return nil end
+
+	return {
+		life = life, trail=p.prev,
+		size = p.size, sizev = 0, sizea = 0,
+
+		x = p.x, xv = 0, xa = 0,
+		y = p.y, yv = 0, ya = 0,
+		dir = p.angle, dirv = 0, dira = 0,
+		vel = p.vel, velv = 0, vela = 0,
+
+		r = 1, rv = 0, ra = 0,
+		g = 1, gv = 0, ga = 0,
+		b = 1, bv = 0, ba = 0,
+		a = 0.5, av = 0, aa = -1/(life^2)*2,
+	}
+end, },
+function(self)
+	if nbp > 0 then
+		nbp = nbp - self.ps:emit(nbp)
+	end
+end,
+nbp, "particles_images/"..img