main.lua

   1 --[[
   2 Batto! A clicking arcade game
   3 Copyright 2018 Pajo <xpio at tut dot by>
   4
   5 This program is free software: you can redistribute it and/or modify
   6 it under the terms of the GNU General Public License as published by
   7 the Free Software Foundation, either version 3 of the License, or
   8 (at your option) any later version.
   9
  10 This program is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU General Public License for more details.
  14
  15 You should have received a copy of the GNU General Public License
  16 along with this program.  If not, see <https://www.gnu.org/licenses/>.
  17 ]]
  18
  19 -- love 11.1
  20
  21 function love.load()
  22         love.window.setMode(1080/2.5, 1920/2.5)
  23         screen = {
  24                 w = love.graphics.getWidth(),
  25                 h = love.graphics.getHeight()
  26         }
  27
  28         player = {
  29                 x = screen.w / 2,
  30                 y = screen.h * 3 / 4,
  31                 size = screen.w / 6,
  32                 draw = function(self)
  33                         love.graphics.setColor(.5, .5, .8)
  34                         love.graphics.circle("fill", self.x, self.y, self.size / 2)
  35                 end,
  36                 move = function(self, x, y)
  37                         if trails[1] then return end -- no movement until all trails expire
  38                         trails:make(x, y, self.x, self.y)
  39                         player.x = x
  40                         player.y = y
  41                 end,
  42                 destroy = function(self)
  43                         game.score = game.score - 10
  44                         explosions:make(self.x, self.y, self.size)
  45                 end,
  46         }
  47
  48         trails = {
  49                 min = 1,
  50                 max = 40,
  51                 duration = 1 / 20,
  52                 timer = 0,
  53                 make = function(self, x, y, sx, sy)
  54                         local expiration = 10
  55                         local d = ((x - sx) ^ 2 + (y - sy) ^ 2) ^ 0.5
  56                         local howmany = math.max(math.min(d / expiration, self.max), self.min)
  57                         local step
  58                         for a = self.min, howmany do
  59                                 step = 1 - a / howmany
  60                                 trails[a] = {
  61                                         size = player.size,
  62                                         x = sx - (sx - x) * step,
  63                                         y = sy - (sy - y) * step
  64                                 }
  65                         end
  66                 end,
  67                 draw = function(self)
  68                         love.graphics.setColor(1, .5, 0)
  69                         for a = 1, #self do
  70                                 love.graphics.circle("line", self[a].x, self[a].y, self[a].size / 2)
  71                         end
  72                 end,
  73                 expire = function(self, dt)
  74                         self.timer = self.timer + dt
  75                         if self.timer > self.duration and #self > 0 then
  76                                 self[#self] = nil
  77                                 self.timer = self.timer - self.duration
  78                         end
  79                 end,
  80                 check = function(self)
  81                         for a = 1, #self do for b = 1, #enemies do
  82                                 if not enemies[b].dying and collides(trails[a], enemies[b]) then
  83                                         if not enemies[b].isbullet then enemies[b]:die() end
  84                                 end
  85                         end end
  86                 end,
  87                 purge = function(self)
  88                         while #self > 0 do self[#self] = nil end
  89                 end,
  90         }
  91
  92         enemies = {
  93                 movements = {
  94                         pass = function(self)
  95                                 self.x = self.x + self.speedx
  96                                 self.y = self.y + self.speedy
  97                                 self.dying = self.dying or
  98                                         (self.x < 1 or self.x > screen.w or self.y < 1 or self.y > screen.h)
  99                                 return self
 100                         end,
 101                         wander = function(self)
 102                                 self.x = self.x + self.speedx
 103                                 self.y = self.y + self.speedy
 104                                 if self.x < 1 or self.x > screen.w then
 105                                         self.speedx = - self.speedx
 106                                 end
 107                                 if self.y < 1 or self.y > screen.h then
 108                                         self.speedy = - self.speedy
 109                                 end
 110                                 return self
 111                         end,
 112                         chase = function(self)
 113                                 self.speedx = self.speedx * 199/200 + (player.x - self.x) / 2000
 114                                 self.speedy = self.speedy * 199/200 + (player.y - self.y) / 2000
 115                                 self.speedx = self.speedx / math.abs(self.speedx) * math.min(3, math.abs(self.speedx))
 116                                 self.speedy = self.speedy / math.abs(self.speedy) * math.min(3, math.abs(self.speedy))
 117                                 self.x = self.x + self.speedx
 118                                 self.y = self.y + self.speedy
 119                                 return self
 120                         end,
 121                 },
 122                 draw = function(self)
 123                         for a = 1, #self do
 124                                 love.graphics.setColor(self[a].kind.color)
 125                                 love.graphics.rectangle("fill", self[a].x - self[a].size / 2, self[a].y - self[a].size / 2, self[a].size, self[a].size)
 126                         end
 127                 end,
 128                 make = function(self, kind, x, y, speedx, speedy)
 129                         self[#self + 1] = {
 130                                 kind = kind, x = x, y = y, speedx = speedx, speedy = speedy,
 131                                 size = kind.size,
 132                                 dying = false,
 133                                 die = function(self)
 134                                         explosions:make(self.x, self.y, self.size)
 135                                         game.score = game.score + 1
 136                                         self.dying = true
 137                                         -- will be disposed of in cleanup
 138                                 end,
 139                         }
 140                 end,
 141                 move = function(self)
 142                         for a = 1, #self do
 143                                 self[a] = self[a].kind.movement(self[a])
 144                         end
 145                 end,
 146                 check = function(self)
 147                         for a = 1, #self do
 148                                 if not self[a].dying and collides(player, self[a]) then
 149                                         player:destroy()
 150                                         self[a]:die()
 151                                 end
 152                         end
 153                         if #self == 0 and game.happened == #scenario[game.level] then
 154                                 endlevel()
 155                         end
 156                 end,
 157                 cleanup = function(self)
 158                         for a = #self, 1, -1 do if self[a].dying then
 159                                 self[a] = self[#self]
 160                                 self[#self] = nil
 161                         end end
 162                 end,
 163         }
 164
 165         enemies.kinds = {
 166                 wanderer = {
 167                         color = {.8, 0, .4},
 168                         movement = enemies.movements.wander,
 169                         size = player.size,
 170                 },
 171                 chaser = {
 172                         color = {1, 0, 0},
 173                         movement = enemies.movements.chase,
 174                         size = player.size,
 175                 },
 176                 passer = {
 177                         color = {0, .5, .8},
 178                         movement = enemies.movements.pass,
 179                         size = player.size,
 180                 },
 181                 bullet = {
 182                         color = {1, 1, 1},
 183                         movement = enemies.movements.pass,
 184                         size = 5,
 185                 },
 186         }
 187
 188         explosions = {
 189                 maxsteps = 15,
 190                 make = function(self, x, y, size)
 191                         self[#self + 1] = {
 192                                 step = 0,
 193                                 x = x,
 194                                 y = y,
 195                                 size = size,
 196                         }
 197                 end,
 198                 grow = function(self)
 199                         -- must go backwards not to disrupt the loop
 200                         for a = #self, 1, -1 do
 201                                 self[a].step = self[a].step + 1
 202                                 if self[a].step > self.maxsteps then
 203                                         self:destroy(a)
 204                                 end
 205                         end
 206                 end,
 207                 destroy = function(self, a)
 208                         self[a] = self[#self]
 209                         self[#self] = nil
 210                 end,
 211                 draw = function(self)
 212                         love.graphics.setColor(1,1,0)
 213                         for a = 1, #self do
 214                                 love.graphics.rectangle("line", self[a].x - self[a].size / 2 - self[a].step * 2,  self[a].y - self[a].size / 2  - self[a].step * 2, self[a].size + self[a].step * 4, self[a].size + self[a].step * 4)
 215                         end
 216                 end,
 217                 purge = function(self)
 218                         while #self > 0 do self[#self] = nil end
 219                 end,
 220         }
 221
 222         origins = {
 223                 ul = { x = 0, y = 0 },
 224                 u = { x = screen.w / 2, y = 0 },
 225                 ur = { x = screen.w, y = 0 },
 226                 l = { x = 0, y = screen.h / 2 },
 227                 c = { x = screen.w / 2, y = screen.h / 2 },
 228                 r = { x = screen.w, y = screen.h / 2 },
 229                 dl = { x = 0, y = screen.h },
 230                 d = { x = screen.w / 2, y = screen.h },
 231                 dr = { x = screen.w, y = screen.h },
 232         }
 233
 234         scenario = {
 235                 --1
 236                 {
 237                         title = "Wave 1",
 238                 player_origin = origins.c,
 239                         --1st enemy
 240                         { time = 0, origin = origins.ul, speed = { 1, 1 }, kind = enemies.kinds.passer },
 241                         --2nd enemy
 242                         { time = 2, origin = origins.l, speed = { 1, 0 }, kind = enemies.kinds.passer },
 243                         --3rd enemy
 244                         { time = 4, origin = origins.dl, speed = { 1, -1 }, kind = enemies.kinds.passer },
 245                         --4th enemy
 246                         { time = 6, origin = origins.d, speed = { 0, -1 }, kind = enemies.kinds.passer },
 247                 },
 248                 --2
 249                 {
 250                         title = "Wave 2",
 251                 player_origin = origins.d,
 252                         --1st enemy
 253                         { time = 0, origin = origins.ul, speed = { 1, 1 }, kind = enemies.kinds.wanderer },
 254                         --2nd enemy
 255                         { time = 1, origin = origins.r, speed = { -5, 0 }, kind = enemies.kinds.bullet },
 256                         --3rd enemy
 257                         { time = 2, origin = origins.l, speed = { 1, 0 }, kind = enemies.kinds.wanderer },
 258                 },
 259                 --3
 260                 {
 261                         title = "Wave 3",
 262                 player_origin = origins.c,
 263                         --1st enemy
 264                         { time = 1, origin = origins.u, speed = { 1, 1 }, kind = enemies.kinds.chaser },
 265                         --2nd enemy
 266                         { time = 2, origin = origins.dr, speed = { 1, 0 }, kind = enemies.kinds.chaser },
 267                         --3rd enemy
 268                         { time = 3, origin = origins.dl, speed = { 1, 0 }, kind = enemies.kinds.chaser },
 269                 },
 270         }
 271
 272         game = {
 273                 timer = 0,
 274                 level = 2,
 275                 happened = 0,
 276                 score = 0,
 277                 mode = "title",
 278         }
 279 end
 280
 281
 282 function collides(obj1, obj2)
 283         local o1x, o1y, o2x, o2y, d
 284         o1x = obj1.x + obj1.size / 2
 285         o1y = obj1.y + obj1.size / 2
 286         o2x = obj2.x + obj2.size / 2
 287         o2y = obj2.y + obj2.size / 2
 288         d = obj1.size / 2 + obj2.size / 2
 289         return (o1x - o2x) ^ 2 + (o1y - o2y) ^ 2 < d ^ 2
 290 end
 291
 292
 293 function beginlevel()
 294         game.timer = 0
 295         game.mode = "play"
 296         game.happened = 0
 297         player.x = scenario[game.level].player_origin.x
 298         player.y = scenario[game.level].player_origin.y
 299 end
 300
 301
 302 function happen(number)
 303         game.happened = number
 304         local s = scenario[game.level][number]
 305         enemies:make(s.kind, s.origin.x, s.origin.y, s.speed[1], s.speed[2])
 306         enemies[#enemies].isbullet = s.kind == enemies.kinds.bullet
 307 end
 308
 309
 310 function endlevel()
 311         trails:purge()
 312         explosions:purge()
 313         game.timer = 0
 314         game.level = game.level + 1
 315         if game.level > #scenario then
 316                 game.mode = "theend"
 317                 game.level = 1
 318         else
 319                 game.mode = "title"
 320         end
 321 end
 322
 323
 324 function love.update(dt)
 325         if dt < 1/50 then
 326                 love.timer.sleep(1/30 - dt)
 327         end
 328         game.timer = game.timer + dt
 329         if game.mode == "play" then
 330                 trails:expire(dt)
 331                 enemies:move()
 332                 enemies:check()
 333                 enemies:cleanup()
 334                 explosions:grow()
 335                 for a = game.happened + 1, #scenario[game.level] do
 336                         if game.timer > scenario[game.level][a].time then
 337                                 happen(a)
 338                         end
 339                 end
 340         elseif game.mode == "title" then
 341                 if game.timer > 3 then
 342                         beginlevel()
 343                 end
 344         end
 345 end
 346
 347
 348 function osd()
 349         love.graphics.setColor(1,1,1)
 350         love.graphics.print(math.floor(game.timer) .. ':' .. game.score, 1, 2)
 351         love.graphics.print('game.mode = ' .. game.mode, 1, 20)
 352         love.graphics.print('#enemies = ' .. #enemies, 1, 30)
 353 end
 354
 355
 356 function love.draw()
 357         if game.mode == "play" then
 358                 trails:draw()
 359                 player:draw()
 360                 enemies:draw()
 361                 explosions:draw()
 362         elseif game.mode == "title" then
 363                 love.graphics.setColor(1,1,1)
 364                 love.graphics.print(scenario[game.level].title, 100, 100)
 365         elseif game.mode == "theend" then
 366                 love.graphics.setColor(1,1,1)
 367                 love.graphics.print('The End', 100, 100)
 368         end
 369         osd()
 370 end
 371
 372
 373 function love.mousepressed(x, y, button)
 374         if game.mode == "title" or game.mode == "theend" then
 375                 beginlevel()
 376         elseif game.mode == "play" then
 377                 player:move(x, y)
 378                 trails:check()
 379         end
 380 end
 381
 382
 383 function love.keypressed(k)
 384         if k == "escape" or k == "q" then
 385                 love.event.push("quit")
 386         end
 387 end