Start Screen: how to select with keys or mouse

Graphics3D 800,600,32

Const WELCOME_SCREEN_PATH$="textures/truewelcome.png"

Const FONT_NAME$="Arial"
Const FONT_SIZE=18


Const STATE_WELCOME=0
Const STATE_MENU_MAIN=1
Const STATE_MENU_OPTIONS=2
Const STATE_GAME_INITIALISE=3
Const STATE_GAME_RUNNING=4
Const STATE_GAME_OVER=5

Global MACHINE_STATE
Global MENU_HIGHLIGHTED=0

Const MENU_MAIN_SELECTIONS=2
Const MENU_OPTIONS_SELECTIONS=3

Const BUTTON_WIDTH=128
Const BUTTON_HEIGHT=48

Global MENU_BUTTONS[MENU_MAIN_SELECTIONS+MENU_OPTIONS_SELECTIONS]

Const BUTTON_MAIN_START=0
Const BUTTON_MAIN_OPTIONS=1

Const BUTTON_OPTIONS_BACK=2
Const BUTTON_OPTIONS_GRAPHICS=3
Const BUTTON_OPTIONS_SOUND=4

Const KEY_SCANCODE_UP=200
Const KEY_SCANCODE_DOWN=208
Const KEY_SCANCODE_SPACE=57
Const KEY_SCANCODE_Q=16

Global KEY_SELECTION_UP=KEY_SCANCODE_UP
Global KEY_SELECTION_DOWN=KEY_SCANCODE_DOWN
Global KEY_SELECTION_GO=KEY_SCANCODE_SPACE

Global IMG_WELCOME_SPLASH

Runtime


Function Initialise()
	;Load Assets here etc.
	
	IMG_WELCOME_SPLASH=LoadImage(WELCOME_SCREEN_PATH$)
	
	Local Font=LoadFont(FONT_NAME,FONT_SIZE)
	SetFont Font
	
	MENU_BUTTONS[BUTTON_MAIN_START]=CreateImage(BUTTON_WIDTH,BUTTON_HEIGHT)
	SetBuffer ImageBuffer(MENU_BUTTONS[BUTTON_MAIN_START])
	Text BUTTON_WIDTH Shr True ,BUTTON_HEIGHT Shr True,"START GAME",True,True
	
	MENU_BUTTONS[BUTTON_MAIN_OPTIONS]=CreateImage(BUTTON_WIDTH,BUTTON_HEIGHT)
	SetBuffer ImageBuffer(MENU_BUTTONS[BUTTON_MAIN_OPTIONS])
	Text BUTTON_WIDTH Shr True,BUTTON_HEIGHT Shr True,"OPTIONS",True,True
	
	
	
	
	
	MENU_BUTTONS[BUTTON_OPTIONS_BACK]=CreateImage(BUTTON_WIDTH,BUTTON_HEIGHT)
	SetBuffer ImageBuffer(MENU_BUTTONS[BUTTON_OPTIONS_BACK])
	Text BUTTON_WIDTH Shr True ,BUTTON_HEIGHT Shr True,"BACK",True,True
	
	MENU_BUTTONS[BUTTON_OPTIONS_GRAPHICS]=CreateImage(BUTTON_WIDTH,BUTTON_HEIGHT)
	SetBuffer ImageBuffer(MENU_BUTTONS[BUTTON_OPTIONS_GRAPHICS])
	Text BUTTON_WIDTH Shr True ,BUTTON_HEIGHT Shr True,"GRAPHICS",True,True
	
	MENU_BUTTONS[BUTTON_OPTIONS_SOUND]=CreateImage(BUTTON_WIDTH,BUTTON_HEIGHT)
	SetBuffer ImageBuffer(MENU_BUTTONS[BUTTON_OPTIONS_SOUND])
	Text BUTTON_WIDTH Shr True ,BUTTON_HEIGHT Shr True,"SOUND",True,True
	
	FreeFont Font
End Function

Function Runtime()
	Initialise
	SetBuffer BackBuffer()
	Main_Loop
	EndGraphics
	End 
End Function

Function Main_Loop()
	
	While (Not(KeyDown(1)))
		StartLoop 
		UpdateLoop
		EndLoop
	Wend
	
End Function

Function StartLoop()
	Cls
End Function

Function UpdateLoop()
	
	Select (MACHINE_STATE)
		Case STATE_WELCOME:
			WelcomeScreen
		Case STATE_MENU_MAIN,STATE_MENU_OPTIONS:
			Menu
		Case STATE_GAME_INITIALISE:
			RuntimeError("Game Has Begun...")
		Case  STATE_GAME_RUNNING:
		Case STATE_GAME_OVER:
	End Select
	
End Function

Function EndLoop()
	Render
End Function

Function Render()
	Flip
End Function

Function Menu()
	
	Local SelectIonStart
	Local SelectionEnd
	
	Select (MACHINE_STATE)
		Case STATE_MENU_MAIN:
			SelectIonStart=BUTTON_MAIN_START
			SelectionEnd=BUTTON_MAIN_OPTIONS
			
		Case STATE_MENU_OPTIONS:
			SelectIonStart=BUTTON_OPTIONS_BACK
			SelectionEnd=BUTTON_OPTIONS_SOUND
			
	End Select
	
	DrawMenuButtons(SelectIonStart,SelectionEnd)
	UpdateMouseSelection(SelectIonStart,SelectionEnd)
	UpdateKeyboardSelection(SelectIonStart,SelectionEnd)
	ShowSelectionRectangle(SelectIonStart,SelectionEnd)
End Function

Function MenuSelectEvent()
	;Responds to Menu Selection and changes Machine State
	Select (MENU_HIGHLIGHTED)
		Case BUTTON_MAIN_START:
			MACHINE_STATE=STATE_GAME_INITIALISE
			
		Case BUTTON_MAIN_OPTIONS:
			MACHINE_STATE=STATE_MENU_OPTIONS
			MENU_HIGHLIGHTED=BUTTON_OPTIONS_BACK
			
		Case BUTTON_OPTIONS_BACK:
			MACHINE_STATE=STATE_MENU_MAIN
			MENU_HIGHLIGHTED=BUTTON_MAIN_START
			
		Case BUTTON_OPTIONS_GRAPHICS:
			;... etc. Not completed here
			
		Case BUTTON_OPTIONS_SOUND:
			;... etc. Not completed here
	End Select
End Function

Function UpdateMouseSelection(SelectionStart,SelectionEnd)
	;Updates Selection based on MouseOver - Can be replaced with ImagesCollide() if using an Image for the pointer
	Local Iter
	
	Local X
	Local Y
	
	Local Count=SelectionEnd-SelectionStart
	
	For Iter=0 To Count
		X=GetXPosition(Iter,Count)		
		Y=GetYPosition(Iter,Count)
		
		If (GetMouseOver(X,Y,BUTTON_WIDTH,BUTTON_HEIGHT))
			DebugLog(Iter)
			MENU_HIGHLIGHTED=Iter+SelectionStart
			
			If (MouseHit(1))
				;Keep this here, so Mouseclick only calls event whilst mouseover
				MenuSelectEvent
			End If	
			
		End If
		
	Next
End Function	

Function UpdateKeyboardSelection(SelectIonStart,SelectionEnd)
	;Updates Selection based on Key Input
	
	Local SelectionChange=KeyHit(KEY_SELECTION_DOWN)-KeyHit(KEY_SELECTION_UP)
	
	If (SelectionChange)
		MENU_HIGHLIGHTED=MENU_HIGHLIGHTED+SelectionChange
		If (MENU_HIGHLIGHTED>SelectionEnd)
			MENU_HIGHLIGHTED=SelectIonStart
		End If
		If (MENU_HIGHLIGHTED<SelectIonStart)
			MENU_HIGHLIGHTED=SelectionEnd
		End If
	End If
	
	If (KeyHit(KEY_SELECTION_GO))
		MenuSelectEvent
	End If
	
End Function	

Function GetMouseOver(x,y,w,h)
	Local mx=MouseX()
	Local my=MouseY()
	Return  (  ((mx>x) And (mx<(x+w)))    And    ((my>y) And (my<(y+h)))  )
End Function

Function ShowSelectionRectangle(SelectionStart,SelectionEnd)
	Rect GetXPosition(SelectionStart,SelectionEnd),GetYPosition(MENU_HIGHLIGHTED-SelectionStart,SelectionEnd),BUTTON_WIDTH,BUTTON_HEIGHT,False
End Function

Function DrawMenuButtons(ButtonStart,ButtonEnd)
		;Draws the buttons from the library
	Local Count=ButtonEnd-ButtonStart
	
	Local Iter
	Local X
	Local Y
	For Iter= 0 To Count
		X=GetXPosition(Iter,Count)
		Y=GetYPosition(Iter,Count)
		DrawImage MENU_BUTTONS[Iter+ButtonStart],X,Y
	Next
End Function		

Function GetXPosition(Item,Count)
	;So the same function can be used for selection rectangle, mouse events and the actual button drawing
	Return (GraphicsWidth() Shr True) - (BUTTON_WIDTH Shr True)
End Function

Function GetYPosition(Item,Count)		
	;So the same function can be used for selection rectangle, mouse events and the actual button drawing
	Return  (BUTTON_HEIGHT*1.5)*(Item+1)
End Function

Function WelcomeScreen()
	DrawImage IMG_WELCOME_SPLASH,(GraphicsWidth() Shr True)-ImageWidth(IMG_WELCOME_SPLASH),(GraphicsHeight() Shr True)-ImageHeight(IMG_WELCOME_SPLASH)
	If ((KeyHit(KEY_SELECTION_GO)) Or MouseHit(1))
		MACHINE_STATE=STATE_MENU_MAIN
	End If
End Function

.start         ;.start is an label, here does the "Gosub start" jumps into.
;game start

A$="Starting"  ;this is the text, which is displayed in my example.It is here,where your game starts.

Return         ;After the Game ends, Return jumps back to the line where Gosub start was called

img_controls=LoadImage("images/controls.png")

Function CheckReturn()
 if keydown(28) or Keydown(57)      ;check if user has pressed the enter or return keys
   while keydown(28) or Keydown(57) ;Wait until user has released the keys
      delay 1
   Wend
   Return 1
 EndIf
 Return 0 
End Function