<\/div>In gamedev, a vector is a variable that stores 3 values: X, Y, and Z. These are used constantly. Every 3D object in the scene is made up of triangles, every triangle is made of 3 points, and every point has a vector to keep track of its position in 3D space. The player’s velocity as they double-jump over lava is stored in a vector. The imaginary line from (the muzzle of the protagonist’s gun) to (the point where the player is aiming) is stored in a vector. Things like mouse and joystick input are often stored in a vectorSometimes the engine you’re working with has 2D vectors for this, but if not the programmer might store the input values in X and Y and leave Z unused.<\/span>. The position of the camera is a vector and the direction the camera is pointing is another vector. Every light in the scene uses a vector to store its position, and directional lightsLike a flashlight or a searchlight.<\/span> will use another vector to keep track of which way the light is pointed.<\/p>\n Nearly every system in a game either contains or manipulates vectors. Sounds come from a location, so they need a vector. Physics involves spatial calculations, so physics objects definitely need vectors. Loading geometry like characters and level data will need vectors. So will particles. Animations. Rendering code. Collision detection. Camera placement. Lighting.<\/p>\n Even if you’re just making a 2D side-scroller, you still need 3D vectors. You need 2 dimensions for the left-right and up-down movement within the game, but you’ll use the Z axis for depth, which you’ll need if you want a parallax<\/a>ingThe background scrolls slower than the foreground to give the scene a feeling of depth.<\/span> background. Even if your game is played on a pure 2D plane with no attempt to create the illusion of depth, you’ll still need some vectors for manipulating the camera because the graphics hardware communicates in vectors and you need that thing to draw the scene.<\/p>\n The thing about vectors is that they don’t come with the language<\/b>. Without a vector data type to handle these values, you’d be forced to juggle the individual X, Y, and Z components:<\/p>\n That’s a lot more verbose and error-prone than this:<\/p>\n That’s a trivial example. The problem gets completely out of control once you start doing real work. I don’t want to say that nobody has ever made a game without vector data types, but I feel confident in saying that doing so would be extremely cumbersome. Everyone making games has to write or import their own vectors. You can’t begin working on a project until you have these.<\/p>\n If you’re going to have vectors, then you’ll also need to be able to manipulate them. You need to be able to add them, subtract them, measure their length, compare them to each other, scale them, copy them, reflect them off each other, and a host of other things.<\/p>\n In addition to vectors, a proper game development environment ought to have a bunch of other stuff. Here are several, in order of descending need from “you can’t do anything useful without this” to “it would be nice to have this”.<\/p>\nplayer_position_x += offset_x;\r\nplayer_position_y += offset_y;\r\nplayer_position_z += offset_z;\r\ndistance_to_origin = sqrt (player_position_x * player_position_x + player_position_y * player_position_y + player_position_z * player_position_z); \r\n<\/pre>\n
player_position += offset;\r\ndistance_to_origin = player_position.Length ();\r\n<\/pre>\n
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