Game Maker Snippets

Game Maker Studio Snippets.txt

#___Resources
#_Game Maker Programming - Wikibooks, open books for an open world - https://en.wikibooks.org/
https://en.wikibooks.org/wiki/Game_Maker_Programming

#_Game Maker Programming/Intro - Wikibooks, open books for an open world - https://en.wikibooks.org/
https://en.wikibooks.org/wiki/Game_Maker_Programming/Intro

#_Game Maker Programming/Creating a room - Wikibooks, open books for an open world - https://en.wikibooks.org/
https://en.wikibooks.org/wiki/Game_Maker_Programming/Creating_a_room

#_GML Overview - https://docs.yoyogames.com/
https://docs.yoyogames.com/source/dadiospice/002_reference/001_gml%20language%20overview/

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#___Tutorial - Perfect Top Down Movement - YouTube
https://www.youtube.com/watch?v=QtNe7clL9rA&list=PLUQ0xH2XyXgHWa-wC1X1q2sG8lzEuqzGe&index=2

Object
	name: obj_player
	add sprite.
	Add step event
	> Control tab > Code

	

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#_Keyboard
//keyboard_check(vk_right)

---
//left right
var xDirection, yDirection;
xDirection = keyboard_check(ord('D')) - keyboard_check(ord('A')); // 0, 1, -1. ord('key') returns 1 if pressed, 0 otherwise.
yDirection = keyboard_check(ord('S')) - keyboard_check(ord('W')); // 1 or -1

x += xDirection;
y += yDirection;


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#_Bullets

obj_bullet
	move_towards_point(mouse_x,mouse_y,10)

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#_HTML5 Export (v1.4) - YouTube - https://www.youtube.com/
https://www.youtube.com/watch?v=GDEMJkeapEU


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#_Score on screen
#_Controller objects - don't appear on screen, control other things
create controller group: r.click Object, create Group, name: Controllers
create obj: contr_main

View: 0,0 = top left.

Room_01:
	Views > Enable the use of views.

Events:
	Create: 
		//add code:
		global.score=0;
	Draw:
		draw_set_colour(c_lime)
		draw_text(view_xview[0]+10, view_yview[0]+10, "Score: "+string(global.score))

Add controller to room:
room_01
> object > controller > contr_main - click to place.
shift + r.click to delete.



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tr - ... is a global built-in and cannot be used as an instance variable

	In Object cont_main, in Event CreateEvent action number 1 at line 1 : "score" is a global built-in and cannot be used as an instance variable
	In Object cont_main, in Event DrawEvent action number 1 at line 2 : "score" is a global built-in and cannot be used as an instance variable
	Compile Failed - Please check the Compile window for any additional information


global.score=0;
//changed to:
global.my_score=0;

draw_set_colour(c_lime)
draw_text(view_xview[0]+10, view_yview[0]+10, "Score: "+string(global.score))

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tr - BSOD - black screen of death

"Enable the use of views" was ticked.


---
NOTE: These messages are normal:
Attempting to set gamepadcount to 12
Unable to find output device "null" defaulting to "AMD HDMI Output (AMD High Definition Audio Device) via DirectSound"
Total memory used = 519973(0x0007ef25) bytes
Pause event has been registered for this frame
Pause event has been unregistered

---
Attempting to set gamepadcount to 12
Unable to find output device "null" defaulting to "Speakers (Realtek High Definition Audio) via DirectSound"
Total memory used = 518809(0x0007ea99) bytes
Pause event has been registered for this frame
Pause event has been unregistered

---
Attempting to set gamepadcount to 12
Unable to find output device "null" defaulting to "AMD HDMI Output (AMD High Definition Audio Device) via DirectSound"
Total memory used = 525485(0x000804ad) bytes
Pause event has been registered for this frame
Pause event has been unregistered
Pause event has been registered for this frame
Pause event has been unregistered


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#___Keyboard shortcuts

search scripts: Ctrl+shift+F

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#_room - change start/default room
https://docs.yoyogames.com/source/dadiospice/002_reference/rooms/room_goto.html

first room in list loads first.
Drag room to heading "Rooms".

room_goto()

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#_collision

add event collision object > obj_bullet

//destroys the bullet.
// "other" - is the object selected when the event was added. eg. Event > collision > player.
with(other) instance_destroy();

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#_check if object exists / object_exists()


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#_spawn_rate

spawn_rate = random_range(60, 180);
alarm[0] = spawn_rate;



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#_Esoteric Software - https://github.com/
https://github.com/EsotericSoftware

#_2D skeletal animation runtimes for Spine.

#_Esoteric Software - https://github.com/
https://github.com/EsotericSoftware
#_EsotericSoftware/spine-runtimes: 2D skeletal animation runtimes for Spine. - https://github.com/
https://github.com/EsotericSoftware/spine-runtimes

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#___SDK - Docs

#_point_direction - https://docs.yoyogames.com/
https://docs.yoyogames.com/source/dadiospice/002_reference/maths/vector%20functions/point_direction.html
- angle between 2x x&y coordinates.

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#_Set angle of 3d viewport

move_towards_point(mouse_x,mouse_y,10)
angle =(point_direction(x,y,mouse_x,mouse_y))
d3d_transform_set_rotation_axis(angle, angle, angle, angle)

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#_rotate sprite

image_angle = point_direction(x, y, mouse_x, mouse_y);

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#_json examples
#_GameMaker Tutorials: Using JSON Data - http://jasonleeelliott.com/
http://jasonleeelliott.com/using-json-data/
var theCard = instance_create(320-CARD_CENTER,32,obj_Card);

var theCard = instance_create(320,32,obj_Card);
theCard.myID = 1;


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#_GM2 - switch between drag and drop and gml

r.click code > convert to dnd

r.click title bar > convert to GML

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#_move enemy/object towards player

with (other) {
  if (hp <= 0) {
    instance_destroy();
    global.my_score += 5;
  }
  move_towards_point(global.playerX, global.playerY, global.enemySpeed);
  if (global.dead) {
    instance_destroy();
  }
}

---
https://forum.yoyogames.com/index.php?threads/make-an-object-go-towards-an-object.3441/

move_towards_point( player_obj.x, player_obj.y, 4 ); 
move_towards_point( obj_player.x, obj_player.y, 4 ); 

direction = point_direction(x,y,obj_player.x,obj_player.y);

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#_basic enemy AI
#_GameMaker - Basic Enemy AI (cont...) - YouTube - https://www.youtube.com/
https://www.youtube.com/watch?v=MlBt5FU0Eeo&list=PLUQ0xH2XyXgHWa-wC1X1q2sG8lzEuqzGe&index=6

scripts
states

---
obj_enemy_Create:
	//globally reference a script
	state = scr_enemy_static;

	//Variables
	hp = 100;
	enemySpeed = 2;
	aggroRange = 120;

---
#obj enemy step (contain a var called state)

//states
scipt_execute(state); //all enemies can call this script to control their movement.

//move towards player
//This function moves an instance towards a point avoiding obstacles.
mp_potential_step(obj_player.x,obj_player.y, enemySpeed, true);

---
New Script > scr_enemy_static

var dis = point_distance(x,y,obj_player.x,obj_player.y);


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#_move player - Basic movement of player left right, up, down
All versions.

sprite
room
object: create obj_player, select sprite, add obj_player to room.
obj_player: add event: Step > Control > Code:

---
// Complex code:
//left right, up, down
var xDirection, yDirection;
xDirection = keyboard_check(ord("D")) - keyboard_check(ord("A")); // 0, 1, -1. ord('key') returns 1 if pressed, 0 otherwise.
yDirection = keyboard_check(ord("S")) - keyboard_check(ord("W")); // 1 or -1

global.walkingSpeed = 3;
x += xDirection * global.walkingSpeed;
y += yDirection * global.walkingSpeed;

//add these so other scripts know where the player is
global.playerX = x
global.playerY = y

---
Simpler Code:

//left right
var xDirection, yDirection;
xDirection = keyboard_check(ord('D')) - keyboard_check(ord('A')); // 0, 1, -1. ord('key') returns 1 if pressed, 0 otherwise.
yDirection = keyboard_check(ord('S')) - keyboard_check(ord('W')); // 1 or -1

x += xDirection;
y += yDirection;


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tr - Unexpected symbol in expression
COMPILATION ERROR in code action
Error in code at line 14:
   var xDirection = 0;
                  ^
at position 17: Unexpected symbol in expression.

// variable was declared twice
var xDirection = 0;
var xDirection = 0;

---
//ok
	if (a==0)
//wrong
	if (a===0)

---
ERROR in
action number 1
of  Step Event
for object obj_player:

Error in code at line 19:
   x += xDirection;
        ^
at position 7: Unknown variable xDirection

---
//ok
var xDirection;
xDirection = 0;
x += xDirection;

//wrong - MUST give a variable a value before using it!
var xDirection;
x += xDirection;


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