Difference between revisions of "2D Space Shooter Part 4: Player"
(2 intermediate revisions by the same user not shown) | |||
Line 2: | Line 2: | ||
It is time to make our ship controllable. Since only the player's ship will be controllable, let's make a subclass of our generic Ship to handle that. We will call it 'PlayerShip'. | It is time to make our ship controllable. Since only the player's ship will be controllable, let's make a subclass of our generic Ship to handle that. We will call it 'PlayerShip'. | ||
− | Go ahead and create a new file named 'player.lua' | + | Go ahead and create a new file named '''player.lua''', this new file will depend on the Ship class. There are two methods to implement code dependency in Gideros Studio: |
+ | # right click on the file name and access 'Code dependencies'. From there tell Gideros that player.lua will depend on ships.lua | ||
+ | # by code by adding ''--!NEEDS:your_file.lua'' at the top of a file | ||
== Player control == | == Player control == | ||
− | The code | + | The code of this file is rather simple: we register mouse events and react upon them: |
<syntaxhighlight lang="lua"> | <syntaxhighlight lang="lua"> | ||
− | PlayerShip=Core.class(Ship) | + | --!NEEDS:ships.lua |
+ | PlayerShip = Core.class(Ship) | ||
function PlayerShip:init() | function PlayerShip:init() | ||
− | self:addEventListener(Event.MOUSE_DOWN,self.onMouseDown,self) | + | self:addEventListener(Event.MOUSE_DOWN, self.onMouseDown, self) |
− | self:addEventListener(Event.MOUSE_UP,self.onMouseUp,self) | + | self:addEventListener(Event.MOUSE_UP, self.onMouseUp, self) |
− | self:addEventListener(Event.MOUSE_MOVE,self.onMouseMove,self) | + | self:addEventListener(Event.MOUSE_MOVE, self.onMouseMove, self) |
− | self:addEventListener(Event.MOUSE_HOVER,self.onMouseMove,self) | + | self:addEventListener(Event.MOUSE_HOVER, self.onMouseMove, self) |
end | end | ||
function PlayerShip:destroy() | function PlayerShip:destroy() | ||
− | self:removeEventListener(Event.MOUSE_DOWN,self.onMouseDown,self) | + | self:removeEventListener(Event.MOUSE_DOWN, self.onMouseDown, self) |
− | self:removeEventListener(Event.MOUSE_UP,self.onMouseUp,self) | + | self:removeEventListener(Event.MOUSE_UP, self.onMouseUp, self) |
− | self:removeEventListener(Event.MOUSE_MOVE,self.onMouseMove,self) | + | self:removeEventListener(Event.MOUSE_MOVE, self.onMouseMove, self) |
− | self:removeEventListener(Event.MOUSE_HOVER,self.onMouseMove,self) | + | self:removeEventListener(Event.MOUSE_HOVER, self.onMouseMove, self) |
− | -- | + | -- call the inherited destructor |
Ship.destroy(self) | Ship.destroy(self) | ||
end | end | ||
function PlayerShip:onMouseDown(event) | function PlayerShip:onMouseDown(event) | ||
− | + | self.fire=true -- start firing | |
− | self.fire=true | ||
end | end | ||
function PlayerShip:onMouseUp(event) | function PlayerShip:onMouseUp(event) | ||
− | + | self.fire=false -- stop firing | |
− | self.fire=false | ||
end | end | ||
function PlayerShip:onMouseMove(event) | function PlayerShip:onMouseMove(event) | ||
− | -- | + | -- clamp the player ship position to something in the screen |
− | local x=(event.x<>(SCR_LEFT+64))><(SCR_RIGHT-64) | + | local x = (event.x<>(SCR_LEFT+64))><(SCR_RIGHT-64) |
− | local y=(event.y<>(SCR_TOP+64))><(SCR_BOTTOM-64) | + | local y = (event.y<>(SCR_TOP+64))><(SCR_BOTTOM-64) |
− | self:setPosition(x,y) | + | self:setPosition(x, y) |
+ | end | ||
+ | |||
+ | function PlayerShip:explode() | ||
+ | -- here we could show some explosion animation and play a sound | ||
+ | print("\nMISSION FAILED!\n") | ||
+ | self:destroy() | ||
end | end | ||
</syntaxhighlight> | </syntaxhighlight> | ||
− | Notice how we explicitly call the Ship.destroy() function from our subclass. Also note another use of the <> et >< Gideros operators when clamping the player ship position on screen. | + | Notice when the player ship explodes, how we explicitly call the Ship.destroy() function from our subclass. Also note another use of the <> et >< Gideros operators when clamping the player ship position on screen. |
== Using our controllable ship == | == Using our controllable ship == | ||
− | This is were OOP | + | This is were OOP really shines. The only thing you need to do to make the ship you added to main.lua controllable is just to instanciate a PlayerShip instead of a generic Ship. In main.lua, change: |
<syntaxhighlight lang="lua"> | <syntaxhighlight lang="lua"> | ||
− | + | local player = Ship.new() | |
</syntaxhighlight> | </syntaxhighlight> | ||
into: | into: | ||
<syntaxhighlight lang="lua"> | <syntaxhighlight lang="lua"> | ||
− | + | local player = PlayerShip.new() | |
</syntaxhighlight> | </syntaxhighlight> | ||
− | |||
− | |||
{{#widget:GApp|app=SpaceShooter_PL1.GApp|width=320|height=480|plugins=bump}} | {{#widget:GApp|app=SpaceShooter_PL1.GApp|width=320|height=480|plugins=bump}} | ||
− | + | Prev.: [[2D_Space_Shooter_Part_3:_Ships]]</br> | |
'''Next: [[2D Space Shooter Part 5: Firing]]''' | '''Next: [[2D Space Shooter Part 5: Firing]]''' | ||
+ | |||
+ | '''[[Tutorial - Making a 2D space shooter game]]''' | ||
{{GIDEROS IMPORTANT LINKS}} | {{GIDEROS IMPORTANT LINKS}} |
Latest revision as of 22:11, 15 November 2023
It is time to make our ship controllable. Since only the player's ship will be controllable, let's make a subclass of our generic Ship to handle that. We will call it 'PlayerShip'.
Go ahead and create a new file named player.lua, this new file will depend on the Ship class. There are two methods to implement code dependency in Gideros Studio:
- right click on the file name and access 'Code dependencies'. From there tell Gideros that player.lua will depend on ships.lua
- by code by adding --!NEEDS:your_file.lua at the top of a file
Player control
The code of this file is rather simple: we register mouse events and react upon them:
--!NEEDS:ships.lua
PlayerShip = Core.class(Ship)
function PlayerShip:init()
self:addEventListener(Event.MOUSE_DOWN, self.onMouseDown, self)
self:addEventListener(Event.MOUSE_UP, self.onMouseUp, self)
self:addEventListener(Event.MOUSE_MOVE, self.onMouseMove, self)
self:addEventListener(Event.MOUSE_HOVER, self.onMouseMove, self)
end
function PlayerShip:destroy()
self:removeEventListener(Event.MOUSE_DOWN, self.onMouseDown, self)
self:removeEventListener(Event.MOUSE_UP, self.onMouseUp, self)
self:removeEventListener(Event.MOUSE_MOVE, self.onMouseMove, self)
self:removeEventListener(Event.MOUSE_HOVER, self.onMouseMove, self)
-- call the inherited destructor
Ship.destroy(self)
end
function PlayerShip:onMouseDown(event)
self.fire=true -- start firing
end
function PlayerShip:onMouseUp(event)
self.fire=false -- stop firing
end
function PlayerShip:onMouseMove(event)
-- clamp the player ship position to something in the screen
local x = (event.x<>(SCR_LEFT+64))><(SCR_RIGHT-64)
local y = (event.y<>(SCR_TOP+64))><(SCR_BOTTOM-64)
self:setPosition(x, y)
end
function PlayerShip:explode()
-- here we could show some explosion animation and play a sound
print("\nMISSION FAILED!\n")
self:destroy()
end
Notice when the player ship explodes, how we explicitly call the Ship.destroy() function from our subclass. Also note another use of the <> et >< Gideros operators when clamping the player ship position on screen.
Using our controllable ship
This is were OOP really shines. The only thing you need to do to make the ship you added to main.lua controllable is just to instanciate a PlayerShip instead of a generic Ship. In main.lua, change:
local player = Ship.new()
into:
local player = PlayerShip.new()
Prev.: 2D_Space_Shooter_Part_3:_Ships
Next: 2D Space Shooter Part 5: Firing
Tutorial - Making a 2D space shooter game