[nit.git] / examples / mnit_dino / src / game_logic.nit

# This file is part of NIT ( http://www.nitlanguage.org ).
#
# Copyright 2012-2013 Alexis Laferrière <alexis.laf@xymus.net>
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

# Entire game logic for the Dino game
# Depends only on Nit standard library
module game_logic

interface Turnable
        fun do_turn( turn : Turn ) is abstract
end

class Game
        var nbr_wanted_cavemen : Int

        var dino = new Dino
        var cavemen = new Array[Caveman]
        var javelins_in_air = new Array[Javelin]
        var javelins_on_ground = new Array[Javelin]
        var entities = new Array[Entity].with_items(dino)
        var turn_nbr = 0

        var over_since = 0

        var random_radius_min = 200
        var random_radius_max = 400
        protected var random_radius_diff : Int =
                random_radius_max - random_radius_min

        init( cavemen_nbr : Int )
        do
                srand

                nbr_wanted_cavemen = cavemen_nbr

                for n in [0..nbr_wanted_cavemen[ do
                        var man = new Caveman
                        cavemen.add( man )
                        entities.add( man )

                        var radius = (random_radius_min + random_radius_diff.rand).to_f
                        var angle = (2.0*pi).rand
                        man.pos.x = ( angle.cos * radius ).to_i
                        man.pos.y = ( angle.sin * radius ).to_i
                end
        end

        fun do_turn : Turn
        do
                turn_nbr += 1
                var turn = new Turn( self )

                dino.do_turn( turn )
                for man in cavemen do
                        man.do_turn( turn )
                        if not man.is_alive then
                                cavemen.remove( man )
                        end
                end

                for j in javelins_in_air do
                        j.do_turn( turn )
                        if j.hit_dino then
                                javelins_in_air.remove( j )
                                entities.remove( j )
                        else if j.hit_ground then
                                javelins_in_air.remove( j )
                                javelins_on_ground.add( j )
                        end
                end

                if over and over_since == 0 then
                        over_since = turn.nbr
                end

                # sort for blitting, firsts and in the back
                entities.sort !cmp( a, b ) = b.pos.y <=> a.pos.y

                return turn
        end

        fun add_javelin( j : Javelin )
        do
                javelins_in_air.add( j )
                entities.add( j )
        end

        fun over : Bool do return dino.life <= 0 or cavemen.is_empty
        fun won : Bool do return cavemen.is_empty and dino.is_alive
        fun lost : Bool do return not won

        fun ready_to_start_over : Bool do return over_since + 80 < turn_nbr
end

class Turn
        var game : Game
        var nbr : Int

        init ( g : Game )
        do
                game = g
                nbr = game.turn_nbr
        end
end

class GamePos
        var x : Int
        var y : Int

        init ( x, y : Int )
        do
                self.x = x
                self.y = y
        end

        init copy( src : GamePos )
        do
                x = src.x
                y = src.y
        end

        fun squared_dist_with( other : GamePos ) : Int
        do
                var dx = other.x - x
                var dy = other.y - y

                return dx*dx + dy*dy
        end

        redef fun to_s do return "<{x}|{y}>"
end

class Entity
        super Turnable

        var pos = new GamePos( 0, 0 )

        fun squared_dist_with_dino( game : Game ) : Int
        do
                return pos.squared_dist_with( game.dino.pos )
        end
end

class MovingEntity
        super Entity

        var going_to : nullable GamePos writable = null

        fun speed : Int is abstract

        var going_left = false
        var going_right = false

        redef fun do_turn( t )
        do
                if going_to != null then
                        var ds = pos.squared_dist_with( going_to.as(not null) )
                        if ds < speed*speed then
                                going_to = null # is there
                        else
                                var dx = going_to.x - pos.x
                                var dy = going_to.y - pos.y
                                var a = atan2( dy.to_f, dx.to_f )
                                var mx = a.cos*speed.to_f
                                var my = a.sin*speed.to_f

                                pos.x += mx.to_i
                                pos.y += my.to_i

                                going_left = mx < 0.0
                                going_right = mx > 0.0
                        end
                end
        end
end

class MortalEntity
        super Entity

        fun is_alive : Bool is abstract
end

class Dino
        super MovingEntity
        super MortalEntity

        #var running_until = 0
        var total_life = 20
        var life : Int = total_life

        redef fun speed do return 8

        redef fun is_alive do return life > 0

        fun hit( hitter : Entity, damage : Int )
        do
                if is_alive then
                        life -= damage
                end
        end

        redef fun do_turn( t )
        do
                if is_alive then
                        super
                end
        end
end

class Caveman
        super MovingEntity
        super MortalEntity

        var afraid_until = 0
        var cannot_throw_until = 0

        var throw_distance : Int = 400*40+10.rand
        var fear_distance : Int = 300*20+8.rand
        var flee_distance : Int = 600*60+16.rand
        var run_over_distance = 500

        var fear_duration : Int = 80+40.rand
        var throw_period : Int = 40+8.rand

        redef var is_alive : Bool = true

        redef fun speed do return 4

        fun is_afraid( turn : Turn ) : Bool do return turn.nbr < afraid_until
        fun can_throw( turn : Turn ) : Bool do return cannot_throw_until < turn.nbr

        redef fun do_turn( t )
        do
                if is_alive then
                        var dwd = squared_dist_with_dino( t.game )

                        if dwd < run_over_distance then
                                is_alive = false
                                return
                        else if is_afraid( t ) then
                                # going to destination
                        else if t.game.dino.life <= 0 then
                                # dino is dead, chill
                        else
                                if dwd < fear_distance then
                                        afraid_until = t.nbr + fear_duration

                                        var dino_pos = t.game.dino.pos
                                        var dx = dino_pos.x - pos.x
                                        var dy = dino_pos.y - pos.y
                                        var a = atan2( dy.to_f, dx.to_f )
                                        a += pi # get opposite
                                        var x = a.cos*flee_distance.to_f
                                        var y = a.sin*flee_distance.to_f
                                        going_to = new GamePos( x.to_i, y.to_i )
                                else if dwd < throw_distance then
                                        if can_throw( t ) then
                                                cannot_throw_until = t.nbr + throw_period
                                                var javelin = new Javelin( pos, t.game.dino.pos )
                                                t.game.add_javelin( javelin )
                                                going_to = null
                                        end
                                else
                                        # get closer to dino
                                        going_to = t.game.dino.pos
                                end
                        end

                        super
                end
        end
end

class Javelin
        super Entity

        var z = 400
        var angle : Float = pi/2.0

        var thrown_angle_xy : Float
        #var thrown_angle_z
        var speed_z = 60

        var hit_ground = false
        var hit_dino = false

        var speed : Int = 10+2.rand
        var hit_dino_distance = 128
        var hit_damage = 1
        var gravity : Int = -3

        init ( from : GamePos, to : GamePos )
        do
                var dx = to.x-from.x
                var dy = to.y-from.y
                thrown_angle_xy = atan2( dy.to_f, dx.to_f )
                pos = new GamePos.copy( from )
        end

        redef fun do_turn( t )
        do
                var dwd = squared_dist_with_dino( t.game )
                if dwd < hit_dino_distance and t.game.dino.is_alive then
                        t.game.dino.hit( self, hit_damage )
                        hit_dino = true
                else
                        if z <= 0 then
                                hit_ground = true
                        else
                                # in the air
                                speed_z += gravity
                                z += speed_z

                                var mx = (thrown_angle_xy.cos * speed.to_f).to_i
                                pos.x += mx
                                pos.y += (thrown_angle_xy.sin * speed.to_f).to_i

                                if mx > 0 then
                                        angle = atan2( (speed_z/10).to_f, -1.0*speed.to_f )-pi/2.0
                                else
                                        angle = atan2( (speed_z/10).to_f, speed.to_f )-pi/2.0
                                end
                        end
                end
        end
end