starship (TIC-80 source)

-- title:  starship
-- author: wesley werner
-- desc:   for ludum dare #39, theme:
--          running out of power.
--       you pilot a starship and recharge
--       your fuel cells from solar radiation.
--       z: shields
--   x: fire phasers
-- script: lua

IDDQD=false

-- screen size in pixels
MAP_W=240
MAP_H=136

-- screen size in map cells
CELLS_W=MAP_W/8
CELLS_H=MAP_H/8

-- other wessels in play
MAX_WESSELS=30

-- minimum distance for attack
FIRING_RANGE=4

SFX_BEAM=4
SFX_CHARGE=2
SFX_EXPLODE=3

-- ticks to pass before closing a message box
READ_TIMEOUT=100

t=0

-- variables
state="intro"
mapx=90
mapy=50
wessels={}
plr=nil
stars={}
suns=nil
hazards={}
planets=nil
mission=nil

-- each new mission destination planet
-- gets a name and this list is reduced.
-- when all names are used up the game
-- is won. there is a chance that a
-- planet is called upon again, in that
-- case the names list is not reduced.
planet_names={
 "Hadrian",
 "Knara Prime",
 "Frixion Prime",
 "Epona",
 "Zelos",
 "Carina 3",
 "Vendrizi 9",
 "Beta Atheni",
 "Helion 8",
 "Arkanna",
}

mission_types={
 {note="escort ambassador Spock",
     result="He says to live long and prosper"},
    {note="transport some medical supplies",
     result="You join them in a celebratory meal"},
    {note="deliver much needed vacines",
     result="The planet rejoyces at your arrival"},
    {note="deliver sealed containers",
     result="You get a brief thanks"},
    {note="escort admiral kurtz",
     result="You receive his gratitude"},
    {note="transport plasma infusers",
     result="You feel pretty good about it"},
    {note="escort ambassador Sarek",
     result="He asks somberly about Spock"},
    {note="deliver some food rations",
     result="You are praised for your effort"},
    {note="locate missing commander Data",
     result="He was rescued from mercinaries"},
}


function init_wessels()
 -- define the wessels in play.
    -- the player is wessel 1 and has a
    -- unique position - it stays centred
    wessels[1]={
        sprite=256,
        x=105,  -- position in map coords
        y=60,
        speed=1,    -- move speed
        xvel=0, -- movement velocity
        yvel=0,
        power=100
        }

 --AI WESSELS
    for i=2,MAX_WESSELS do
        wessels[i]={
            sprite=272,
            x=math.floor(math.random()*MAP_W),
            y=math.floor(math.random()*MAP_H),
            speed=0.1,  -- move speed
            xvel=0, -- movement velocity
            yvel=0,
            power=50
            }
    end

end


function init_player()

    plr=wessels[1]

end


function init_hazards()

    -- define hazardous tiles

    -- speed=factor (0 blocks)

    local ice={
        name="ice nebula",
        speed=0.5,
        }

    local fire={
        name="fire nebula",
        speed=0.2,
        }

    local elec={
     name="electric nebula",
        speed=0.7,
        }

    hazards={
     [145]=ice,
     [160]=ice,
     [161]=ice,
     [162]=ice,
     [177]=ice,

        [148]=fire,
        [163]=fire,
        [164]=fire,
        [165]=fire,
        [180]=fire,

  [151]=elec,
  [166]=elec,
  [167]=elec,
  [168]=elec,
  [183]=elec,

    }

end


function engage()
 trace("warp factor 5 engage!")
 init_planets()
    init_suns()
    init_stars()
    init_wessels()
    init_player()
    init_hazards()
end


function init_stars()
 local n=30
 for i=1,n do
     stars[i]={
                x=math.random() * MAP_W,
                y=(i/n) * MAP_H,
                c=i%4==0 and 2 or i%9==0 and 8 or 3
        }
 end
end


function init_planets()

 -- catalogue planets on the map
    planets={}

    local sprites={
     [48]=true,
     [50]=true,
     [52]=true,
     [54]=true,
     [56]=true,
     [58]=true
    }

    for x=1,MAP_W do
     for y=1,MAP_H do
         local i=mget(x,y)
            if sprites[i] then
             table.insert(planets,{x=x,y=y,name=name})
            end
     end
    end

end


function init_suns()

 -- catalogue suns on the map
    suns={}

    local sprites={
     [16]=true,
        [18]=true,
        [20]=true,
        [22]=true,
        [24]=true,
        [26]=true,
        [28]=true,
    }

    for x=1,MAP_W do
     for y=1,MAP_H do
         local i=mget(x,y)
            if sprites[i] then
             table.insert(suns,{x=x,y=y,power=100})
            end
     end
    end

end


function update_suns()
 -- suns generate power
 if t%30==0 then
     for k,v in pairs(suns) do
         if v.power<100 then
             v.power = v.power+1
            end
    end
 end
end


function update_stars()

    for k,v in pairs(stars) do

     -- move as parallax to luminosity
        v.x = v.x - (v.c * plr.xvel * 0.01)
        v.y = v.y - (v.c * plr.yvel * 0.01)

        -- wrap stars
        if v.x<0 then
            v.x=MAP_W
        elseif v.x>MAP_W then
         v.x=0
        end
        if v.y<0 then
         v.y=MAP_H
        elseif v.y>MAP_H then
         v.y=0
        end

    end

end


function draw_sunpower()
    for k,v in pairs(suns) do
     if v.power>0 and in_view(v.x,v.y) then
         local color=14+(t%60)/30
            local x=8*(v.x-mapx+0.9)
            local y=8*(v.y-mapy+1.5)
            local radius=(v.power/100)*8+8
      circb(x,y,radius,color)
        end
    end
end


function draw_stars()
 for k,v in pairs(stars) do
     pix(v.x, v.y, v.c)
    end
end


function handle_input()

 if state=="play" then

    local delay = 6

        -- move left or right
        if btn(2) then
            plr.xvel=-plr.speed
        elseif btn(3) then
         plr.xvel=plr.speed
        else
         plr.xvel=0
        end

     -- move up or down
        if btn(0) then
            plr.yvel=-plr.speed
        elseif btn(1) then
         plr.yvel=plr.speed
        else
         plr.yvel=0
        end

        -- firing
        if btn(5) then
         plr.firing=true
         plr.shielded=false
        elseif btn(4) then
         plr.shielded=true
         plr.firing=false
        else
         plr.shielded=false
            plr.firing=false
        end

    elseif state=="mission review" then

        if t>READ_TIMEOUT then
         if btn()~=0 then
          state="play"
         end
        end

    elseif state=="mission success" then

        if t>READ_TIMEOUT then
         if btn()~=0 then
             mission=nil
                -- no more planet names left for
                -- missions means game win!
                if #planet_names==0 then
                 state="win"
                else
           state="play"
                end
         end
        end

 elseif state=="intro" then
        if t>READ_TIMEOUT then
         if btn()~=0 then
       state="play"
            end
        end
 end

end


function track_map()

 -- map tracks the player
    if plr.xvel or plr.yvel then
        mapx=math.floor(plr.x)-(CELLS_W/2)%MAP_W
        mapy=math.floor(plr.y)-(CELLS_H/2)%MAP_H
    end

end


-- WESSEL MOVEMENT
function update_wessels()

 if t%10==0 then

     for i=#wessels,1,-1 do

            local v=wessels[i]

            if i>1 then
             move_ai(v)
                if v.destroyed then
                 table.remove(wessels,i)
                    sfx(SFX_EXPLODE,"C-2",60)
                end
            end

            local x = v.x
            local y = v.y

      -- accelerate the wessel
            x=(x+v.xvel)%MAP_W
            y=(y+v.yvel)%MAP_H

            -- store orientation
            if v.xvel~=0 then
                v.orient = v.xvel<0 and 1 or 0
            end

         -- check for blocker sprites
            local m=mget(x,y)
            local hazard = hazards[m]

            if hazard then
             v.hazard_note=hazard.name
                if hazard.speed == 0 then
                 -- blocks movement
                    v.xvel = 0
                    v.yvel = 0
                    x = v.x
                    y = v.y
                elseif hazard.speed then
                 -- affects movement
           x = v.x + (v.xvel * hazard.speed)
           y = v.y + (v.yvel * hazard.speed)
                end
            else
             v.hazard_note=nil
            end

                v.x=x
                v.y=y

        end

    end

end


function move_ai(wessel)

 local r=math.random()

    -- random movement
    if r<0.1 then
     wessel.xvel=math.random(-1,1)
    elseif r>0.9 then
     wessel.yvel=math.random(-1,1)
    end

    -- attacks
    local d=dist(wessel.x,wessel.y,plr.x,plr.y)
    if d<FIRING_RANGE then
     -- in firing range
     wessel.firing=true

        -- player takes damage
        if not plr.shielded then
            plr.power=plr.power-5
        end

        -- enemy takes damage
        if plr.firing==true then
         wessel.power=wessel.power-5
        end

        -- enemy destroyed
        if wessel.power<0 then
         wessel.destroyed=true
        end

        -- play sound
        if plr.firing then
            sfx(SFX_BEAM,"C-5",20)
        else
            sfx(SFX_BEAM,"C-4",20)
        end

    else
     wessel.firing=false

    end

end


function draw_wessels()

    -- draw relative to map position
    for i,v in ipairs(wessels) do

     if in_view(v.x, v.y) then

         -- wessel sprite
            spr(v.sprite,
                screenx(v.x),
                screeny(v.y),
                0,  -- colorkey
                2,  -- scale
                v.orient)

            -- enemy wessel is firing
         if i>1 then
                if v.firing==true then

             line(
                     screenx(v.x)+4,
                        screeny(v.y)+4,
                        screenx(plr.x)+4,
                        screeny(plr.y)+4,
                        (t%10)/5+13)

                    -- wessel health bar
                    rectb(
                     screenx(v.x),
                        screeny(v.y),
                        math.max(1,16*(v.power/100)),
                        2,
                        9)

                    -- draw player shield hit
                    if plr.shielded then
                     circb(
                         screenx(plr.x)+8,
                            screeny(plr.y)+8,
                            (t%10)/5+12,
                            11)

                    end
                end
            end

        end

    end

end


function screenx(n)
 -- converts a map tile to screen coord
    return 8*(n-mapx)
end


function screeny(n)
 -- converts a map tile to screen coord
    return 8*(n-mapy)
end


function draw_map()

    map(mapx,mapy,
        30, -- width
        17, -- height
        0,  -- offset x and y
        0,
        0        -- colorkey
    )

end


function draw_sector()

 local x=math.floor((mapx+(CELLS_W/2)%240)/30)+1
    local y=math.floor((mapy+(CELLS_H/2)%136)/17)+1
 print("SECT "..x..":"..y,160,0,7)

    -- minimap
    spr(266,220,0)
    spr(267,228,0)
    spr(282,220,8)
    spr(283,228,8)
    pix(218+(16*x/8),(16*y/8)-2,15)

    -- mission sector
    if mission then
     pix(mission.mapx,mission.mapy,6)
    end

end


function draw_powerbar()

 local pwr=(plr.power/100)*12
    local color=8

    if plr.charging then
        -- charging
        color=11
        print("+",0,1)
    elseif plr.power<30 then
        -- warning
        color=6
        print("!",0,(t%60)/30+1)
    end

 -- battery
 spr(270,8,0,0)
 spr(271,16,0,0)
    rect(9,2,pwr,4,color)

    -- shields
    if not plr.shielded then
    spr(268,26,0,0)
    else
    spr(269,26,0,0)
    end

    -- weapons
    if not plr.firing then
    spr(284,36,0,0)
    else
    spr(285,36,0,0)
    end

    -- print hazard note
    if plr.hazard_note and t%60>30 then
     print(plr.hazard_note,50,0,6)
    end

end


function dist(ax,ay,bx,by)
 local dx=math.pow(ax-bx,2)
 local dy=math.pow(ay-by,2)
 return math.sqrt(dx+dy)
end


function update_poweruse()

 -- player is on a sun
    if t%30==0 and plr.power<100 then
     plr.charging=false
     for k,sun in pairs(suns) do
         if sun.power>0 then
                if in_view(sun.x, sun.y) then
                 -- player is near this sun
                 local d=dist(sun.x,sun.y,plr.x,plr.y)
                    if d<2 then
                     plr.power=plr.power+8
                        sun.power=sun.power-8
                        plr.charging=true
                        sfx(SFX_CHARGE,"E-1",80)
                        -- set sun cooldown
                        if sun.power<0 then
                         sun.power=-100
                        end
                    end
          end
            end
        end
    end

 -- reduce player power while moving
    if t%10==0 and plr.power>0 then
     if plr.xvel~=0 or plr.yvel~=0 then
         plr.power = plr.power-1
        end
    end

    -- shielding and firing
    if t%10==0 then
     if plr.shielded==true then
      plr.power=plr.power-0.3
        elseif plr.firing==true then
      plr.power=plr.power-0.3
        end
    end

    -- death
    if plr.power<=0 then
     state="dead"
        sfx(SFX_EXPLODE,"C-2",120)
    end

end


function in_view(x, y)

 -- returns if the points are in view
 local dx = x-mapx
    local dy = y-mapy

    return dx>-3 and dx <CELLS_W and
        dy>=-3 and dy<CELLS_H

end


function draw_gameover()
 local x=MAP_W/4
    local y=MAP_H/3
 print("GAME OVER",x+1,y,2,false,2)
 print("GAME OVER",x,y,15,false,2)
 print("You ran out of power!",x+1,y*2,1)
 print("You ran out of power!",x,y*2,15)
end


function near_planet()

 -- gets a nearby planet
    for k,v in pairs(planets) do
  if in_view(v.x,v.y) then
         local d=dist(v.x,v.y,plr.x,plr.y)
            if not v.visited and d<2 then
             return v
            end
        end
 end

end


function far_planet()

 -- gets a remotely far planet
    local plan=nil

    while not plan do
     plan=planets[math.random(#planets)]
     local d=dist(plan.x,plan.y,plr.x,plr.y)
        if plan.visited or d<10 then
         plan=nil
        end
    end

    return plan

end


function update_mission()

 -- reduce processing
    if t%100~=0 then return end

 -- find nearby planet
    local planet=near_planet()

    if planet and mission then

    -- test mission success
        if mission.planet==planet.name then
         -- visited planets don't offer new missions
         planet.visited=true
            -- reset t: it controls input timeout
            state="mission success"
            t=0
        end

    elseif planet and not mission then

        -- get a new mission
        mission=mission_types[math.random(#mission_types)]

        -- to a remote planet
        local dest=far_planet()

        -- that should have a name
        if not dest.name then
         dest.name=table.remove(planet_names)
        end

        -- precalculate mission destination
        -- on minimap
     local mapx=math.floor(dest.x/30)+1
        local mapy=math.floor(dest.y/17)+1
        mapx=(16*mapx/8)+218
        mapy=(16*mapy/8)-2

        mission.planet=dest.name
        state="mission review"
        mission.mapx=mapx
        mission.mapy=mapy

        -- reset t: it controls input timeout
        t=0

    end

end


function draw_missionbar()

 -- draw current mission on screen
    if mission then
     printc(mission.note,120,130,3)
    end

end


function draw_box()
     rect(10,10,220,126,1)
     rectb(10,10,220,126,2)
end


function draw_mission_review()

 -- draw a mission review box
    if mission then
     draw_box()
     printc("NEW MISSION:",120,20,15)
     printc(mission.note,120,60,8)
     printc("destination: "..mission.planet,120,70,10)
  if t>READ_TIMEOUT then
      printc("press any key",120,120,7)
        end
 end

end


function draw_mission_success()

 -- draw a mission success box
    if mission then
     draw_box()
     printc("MISSION SUCCESS!",120,20,15)
     printc(mission.note,120,40,8)
     printc("to "..mission.planet,120,50,10)
     printc(mission.result,120,70,8)
  if t>READ_TIMEOUT then
      printc("press any key",120,120,7)
        end
 end

end


--Prints text where x is the center of text.
function printc(s,x,y,c)
 local w=print(s,0,-8)
 print(s,x-(w/2),y,c or 15)
end


function draw_winscreen()
 draw_box()
 printc("After a long journey exploring",120,20,15)
 printc("the galaxy, you retire on the",120,30,15)
 printc("Eden planet, living in comfort",120,40,15)
 printc("while everyone delivers fresh",120,50,15)
 printc("fruit and craft cheeses to you.",120,60,15)
 printc("Ah this is the life!",120,70,14)
 printc("Created by wesley for Ludum Dare #39",120,80,13)
 printc("press ctrl-r to play again",120,128,7)

 -- wessel sprite
    spr(plr.sprite,
        100,
        80,
        0,  -- colorkey
        6,  -- scale
        plr.orient)

end


function draw_intro()

 draw_box()
 printc("Welcome!",120,20,15)
 printc("You are a starship captain, you explore",120,30,15)
 printc("the galaxy and help others on the way.",120,40,15)
 printc("Z key - engage shields",120,50,8)
 printc("X key - fire phasers (auto aims)",120,60,8)
 printc("Fly over suns to recharge your power",120,70,14)
 printc("Dock at planets to complete missions",120,80,14)
 printc("You retire after 10 missions",120,90,15)
 printc("restart the game with ctrl-R",120,100,15)
 printc("Created by wesley for Ludum Dare #39",120,110,13)
 printc("press any key",120,120,7)

 -- shield sprite
    spr(269,190,48,0,1)
 -- weapons sprite
    spr(285,210,58,0,1)

end


function TIC()

    cls(0)

    handle_input()

 if state=="play" then
     update_wessels()
        update_stars()
        update_suns()
        track_map()
        update_poweruse()
        update_mission()
        if IDDQD then plr.power=100 end
    end

    draw_stars()
    draw_sunpower()
    draw_map()
    draw_wessels()
    draw_powerbar()
    draw_missionbar()
    draw_sector()

    if state=="mission review" then
     draw_mission_review()
    elseif state=="mission success" then
     draw_mission_success()
    elseif state=="dead" then
     draw_gameover()
    elseif state=="win" then
     draw_winscreen()
    elseif state=="intro" then
     draw_intro()
    end

    t=t+1
end

engage()