Raycaster API

Team Doomers: Pavel Peev and Dane Ojala

UWB CSS452 with Prof. Kelvin Sung

Winter 2022

Home Tutorial Demos And Conclusion

Module Description:

Our API implements several classes that will be used together to allow users of the game engine to create 3D gameplay using a Raycasting engine. This API allows users of the game engine to quickly implement a retro-3D look, complete with texture support, camera movement, and more. Users can use a RCCamera in conjunction with a GridMap object of textured Tiles to implement basic games with raycast graphics. RCSpriteRenderable objects allow the user to add enemies, pickups, etc. that are rendered by the RCCamera as well.

API Classes Overview:

RCCamera

• Performs Raycasts and displays the result (Creating a 3D effect)
• Extends from Camera, but includes a RCrotation element for tracking the rotation of the RC_Camera (since we can rotate our view left and right)
• Stores the most recent RayCast data so we can determine which RCSpriteRenderable objects need to be drawn

  GridMap

• 2D Grid that defines the world that will be raycasted.
• Consists of textured tiles
• Grid system allows RCCamera to perform optimization when Raycasting

  Tile

• Simple object that can hold 4 textures, one for each side. Used by GridMap to implement textured worlds.

  RCSpriteRenderable

• Defines a sprite that can be rendered by the RCCamera
• Allows the user to implement enemies, pickups, etc.

API Functions

RCCamera API:

RCCamera(wcPos, viewPortArray)

setViewPort(viewPortArray)

• Sets viewport of the RC_Camera (same as the Camera class)

getViewPort()

• Returns viewport array.

getFOV()

• Returns the total angle that raycasts will be performed between (higher number = wider FOV)

setFOV(fov)

• Sets total angle that raycasts will be performed between (higher number = wider FOV)

getResolution()

• Returns the number of raycasts that will be performed (we do X raycasts from left to right, along the horizon line (Raycasting method does not support height)

setResolution(res)

• Sets the number of raycasts that will be performed

setRayCasterAngle(rot)

• Sets the direction that the camera is facing. (the direction raycasts will originate from)

getRayCasterAngle()

• Returns the current rotation of the camera.

moveRayCasterAngle(t)

• Moves the angle of the camera by the specified amount.

setRayCasterPos(pos)

• Sets current position of the camera in WC (location that raycasts originate)

getRayCasterPos()

• Returns current position of the camera in WC.

moveRayCasterForward(d)

• Moves RCCamera’s position forward relative to its current position.

Raycast(GridMap)

• Returns an array of raycasts
• Provides information about hit/no hit, distance of hit, which object was hit.
• This function will be called by GridMap.draw() to determine what parts of the map should actually be drawn

getRayCasts()

• Returns most recent Raycast
• (used by RC_RenderableSprite.draw() to determine whether the sprite is visible)

DrawRays()

• Draws the most recent Raycasts that have been stored by the RCCamera after raycasting onto a GridMap.

getHorizonLine()

• Returns the height of the horizon line the raycaster renders at.

setHorizonLine(height)

• Sets the height of the horizon line the raycaster renders at.

moveHorizonLine(d)

• Moves the height of the horizon line the raycaster renders at.

getFishEye()

setFishEye(b)

• Getter/Setter for whether to use FishEye effect

getRayLengths()

• Returns the lengths (distance to object) of the most recent raycast.
• Useful for determining the distance from the RCCamera to an object, and used when rendering RCSpriteRenderables.

GridMap API:

RC_GridMap(2DArrayOfTiles, xWidth, yWidth, xPos, yPos)

setTiles(2DArrayOfTiles)

• Function for setting the elements of the gridmap

setPosition(xPos, yPos)

• This allows us to change where the gridmap is located in world coordinates (WC)

getWidth()

• Returns the width of the gridmap.

setWidth(w)

• Sets the width of the gridmap.

getHeight()

• Returns the height of the gridmap.

setHeight(h)

• Sets the height of the gridmap.

setPosition()

• Returns WC offset of the gridmap (as set by SetPosition)

getTileAtIndex(x,y)

• Returns the tile at the specified index within the Gridmap

getHeightInTiles()

• Returns the height of the 2D array of tiles

getWidthInTiles()

• Returns the width of the 2D array of tiles

getHeightOfTile()

• Returns the height of a tile in WC units (gridmap’s height in WC / height in tiles)

getWidthOfTile()

• Returns the width of a tile in WC units (gridmap’s width in WC / width in tiles)

Tile API:

Tile(topTexture, bottomTexture, leftTexture, rightTexture)

getTopTexture()

setTopTexture(tex)

getBottomTexture()

setBottomTexture(tex)

getLeftTexture()

setLeftTexture(tex)

getRightTexture()

setRightTexture(tex)

• Setters and getters for the textures of each side of a tile (getters utilized by RCCamera when determining which texture to render onto a tile)

RCSpriteRenderable API:

RC_RenderableSprite(spriteRef)

• Constructor, sets the sprite reference associated with the class instance

getScaleX()

• Returns the X scale that the RCSpriteRenderable is rendered with.

setScaleX(x)

• Sets the X scale that the RCSpriteRenderable is rendered with.

getScaleY()

• Returns the Y scale that the RCSpriteRenderable is rendered with.

setScaleY(y)

• Sets the Y scale that the RCSpriteRenderable is rendered with.

getYOffset()

• Returns Y offset (how high on the screen the RCSpriteRenderable should be rendered)

setYOffset(y)

• Sets Y offset

draw(RC_Camera, position)

• Draws the sprite if visible (RC_Camera’s current raycasts + position + the sprite’s position are both taken into account)