Cheatsheet topic

Cheatsheet

Note: This is very work in progress. The plan is to create a quick reference card with a list of all available commands in `Bullseye2D`.

Member/Method	Description
App Lifecycle
`onCreate()`	Override this method for one-time setup logic when the app starts.
`onUpdate()`	Override this method for game logic that runs every frame.
`onRender()`	Override this method for drawing and rendering operations every frame.
`onSuspend()`	Override this method for logic to execute when the app loses focus or suspends.
`onResume()`	Override this method for logic to execute when the app regains focus or resumes.
`onResize(int width, int height)`	Override this method to handle canvas resize events.
`onLoading()`	Override this to customize the loading screen; return `true` when done loading.
App Properties
`width`	Gets the current width of the game canvas in pixels.
`height`	Gets the current height of the game canvas in pixels.
`updateRate` (getter/setter)	Gets or sets the desired game logic update rate in updates per second.
`showMouse([Images? images, int frame = 0])`	Makes the system mouse cursor visible, optionally with a custom image.
`hideMouse()`	Hides the system mouse cursor.
Accelerometer (`accel`)
`accel.x`	Gets the current acceleration force along the X-axis (in Gs).
`accel.y`	Gets the current acceleration force along the Y-axis (in Gs).
`accel.z`	Gets the current acceleration force along the Z-axis (in Gs).
`accel.requestPermission()`	Asynchronously requests permission to use the accelerometer (mainly for iOS).
`accel.dispose()`	Unregisters accelerometer event listeners.
Audio (`audio`)
`audio.musicPosition`	Gets the current playback position of the music in seconds.
`audio.musicDuration`	Gets the total duration of the current music in seconds.
`audio.musicProgress`	Gets the current music playback progress (0.0 to 1.0).
`audio.musicVolume` (getter/setter)	Gets or sets the global music volume (0.0 to 1.0).
`audio.musicState`	Gets the current state of the music player (e.g., playing, paused).
`audio.initMusicVisualizer([int fftSize = 2048])`	Initializes and returns an `AudioVisualizer` for the currently playing music.
`audio.playSound(Sound sound, {int channel, bool loop, ...})`	Plays a `Sound` object, optionally on a specific channel and/or looped.
`audio.playSoundOnTargetChannels(Sound sound, {List<int>? channels, ...})`	Plays a `Sound` on one of the specified available channels.
`audio.stopChannel(int channelId)`	Stops playback on the specified audio channel.
`audio.pauseChannel(int channelId)`	Pauses playback on the specified audio channel.
`audio.resumeChannel(int channelId)`	Resumes playback on a paused audio channel.
`audio.setVolume(int channelId, double volume)`	Sets the volume (0.0 to 1.0) for a specific audio channel.
`audio.setPan(int channelId, double pan)`	Sets the stereo panning (-1.0 left to 1.0 right) for a specific channel.
`audio.setRate(int channelId, double rate)`	Sets the playback rate for a specific audio channel.
`audio.obtainFreeChannel([List<int>? targetChannels])`	Finds and returns the ID of an available audio channel from the given list.
`audio.playMusic(String path, bool loop, ...)`	Loads and plays music from the given path, optionally looping.
`audio.stopMusic()`	Stops the currently playing music.
`audio.pauseMusic()`	Pauses the currently playing music.
`audio.resumeMusic()`	Resumes the paused music.
Gamepad (`gamepad`)
`gamepad.countDevices()`	Returns the number of currently connected and recognized gamepads.
`gamepad.joyDown(int port, GamepadButton btn)`	Checks if the specified gamepad button on the given port is currently pressed.
`gamepad.joyHit(int port, GamepadButton btn)`	Checks if the specified gamepad button was just pressed in this frame.
`gamepad.joyUp(int port, GamepadButton btn)`	Checks if the specified gamepad button was just released in this frame.
`gamepad.joyX(int port, Joystick joystick)`	Gets the X-axis value (-1.0 to 1.0) of the specified joystick.
`gamepad.joyY(int port, Joystick joystick)`	Gets the Y-axis value (-1.0 to 1.0) of the specified joystick.
`gamepad.joyZ(int port, Trigger trigger)`	Gets the value (0.0 to 1.0) of the specified trigger.
`gamepad.angle(int port, Joystick joystick)`	Gets the angle (0-359 degrees) of the specified joystick.
Graphics (`gfx`)
`gfx.dispose()`	Releases WebGL resources (program, buffers, VAO).
`gfx.clear([double? r, ...])`	Clears the drawing surface with the specified RGBA color.
`gfx.setColor([double r = 1.0, ...])`	Sets the current drawing color using RGBA values (0.0 to 1.0).
`gfx.setColorFrom(Color color)`	Sets the current drawing color using a `Color` (Vector4) object.
`gfx.setBlendMode(BlendMode mode)`	Sets the blending mode for subsequent drawing operations.
`gfx.setLineWidth(double width)`	Sets the width for drawing lines.
`gfx.setViewport(int x, int y, int width, int height)`	Defines the rectangular area of the canvas where rendering will occur.
`gfx.set2DProjection({double x, y, width, height})`	Configures an orthographic projection for 2D rendering.
`gfx.setProjectionMatrix(Matrix4 matrix)`	Sets a custom projection matrix.
`gfx.setScissor(int x, int y, int width, int height)`	Enables and defines a scissor rectangle to clip rendering.
`gfx.resetScissor()`	Disables scissor testing.
`gfx.resetMatrix()`	Resets the current transformation matrix to identity.
`gfx.pushMatrix()`	Saves the current transformation matrix onto a stack.
`gfx.popMatrix()`	Restores the last saved transformation matrix from the stack.
`gfx.transform(double ix, iy, jx, jy, tx, ty)`	Applies a 2D affine transformation to the current matrix.
`gfx.translate(double tx, double ty)`	Translates the current transformation matrix.
`gfx.rotate(double degrees)`	Rotates the current transformation matrix by the given angle in degrees.
`gfx.scale(double sx, double sy)`	Scales the current transformation matrix.
`gfx.drawPoint(double x, double y)`	Draws a single point at the specified coordinates.
`gfx.drawLine(double x1, y1, x2, y2, {ColorList? colors})`	Draws a line between two points, optionally with per-vertex colors.
`gfx.drawLines(List<double> vertices, {ColorList? colors})`	Draws a series of connected lines (line strip).
`gfx.drawRect(double x, y, width, height, {Texture? t, ...})`	Draws a filled rectangle, optionally textured and with per-vertex colors.
`gfx.drawOval(double x, y, rX, rY, {int segments, ...})`	Draws a filled oval or ellipse.
`gfx.drawCircle(double x, y, radius, {int segments, ...})`	Draws a filled circle.
`gfx.drawPoly(List<double> vertices, {List<double>? uvs, ...})`	Draws a filled polygon from a list of vertices.
`gfx.drawTriangle(double x1,y1, x2,y2, x3,y3, u1,v1, ...)`	Draws a textured triangle with specified vertex and UV coordinates.
`gfx.drawTexture(Texture tex, {double? srcX, ...})`	Draws a `Texture` or a portion of it at a specified location and size.
`gfx.measureText(BitmapFont font, String text)`	Calculates the width and height of a string if rendered with a `BitmapFont`.
`gfx.drawText(BitmapFont font, String text, {double x, ...})`	Draws text using a `BitmapFont` with options for alignment and scaling.
`gfx.drawImage(Images frames, [int frame, double x, ...])`	Draws an `Image` (frame) with transformations (position, rotation, scale).
`gfx.flush()`	Forces all batched drawing commands to be submitted to the GPU.
Keyboard (`keyboard`)
`keyboard.keyDown(KeyCodes key)`	Checks if the specified key is currently held down.
`keyboard.keyUp(KeyCodes key)`	Checks if the specified key was just released in this frame.
`keyboard.keyHit(KeyCodes key)`	Checks if the specified key was just pressed in this frame.
`keyboard.keyHitCountSinceLastFrame(KeyCodes key)`	Gets how many times the specified key was pressed since the last frame.
`keyboard.getCharBuffer()`	Returns a string of all characters typed in the current frame.
`keyboard.getChar()`	Retrieves and removes the next typed character from the input queue.
`keyboard.peekChar(int index)`	Retrieves a typed character from the input queue by index without removing it.
Loader (`loader`)
`loader.isEnabled` (getter/setter)	Gets or sets whether the resource loader is active.
`loader.loadingSequenceFinished` (getter/setter)	Gets or sets if the `onLoading` method has indicated completion.
`loader.loaded`	Gets the total number of bytes loaded so far across all tracked items.
`loader.total`	Gets the total number of bytes for all tracked items.
`loader.done`	Returns `true` if all loading is complete or the loader is disabled.
`loader.allItemsFinished`	Returns `true` if all individual items have finished loading or failed.
`loader.length`	Gets the number of items currently being tracked by the loader.
`loader.percent`	Gets the overall loading progress as a value between 0.0 and 1.0.
Mouse (`mouse`)
`mouse.x`	Gets the current X-coordinate of the mouse cursor relative to the canvas.
`mouse.y`	Gets the current Y-coordinate of the mouse cursor relative to the canvas.
`mouse.scaleX`	Gets the horizontal scaling factor for mouse coordinates.
`mouse.scaleY`	Gets the vertical scaling factor for mouse coordinates.
`mouse.mouseWheel`	Gets the mouse wheel scroll delta for the current frame (+1, -1, or 0).
`mouse.mouseDown(MouseButton button)`	Checks if the specified mouse button is currently held down.
`mouse.mouseHit(MouseButton button)`	Checks if the specified mouse button was just pressed in this frame.
`mouse.mouseUp(MouseButton button)`	Checks if the specified mouse button was just released in this frame.
`mouse.touchDown(int touchIndex)`	Checks if the touch point at the given index is currently active.
`mouse.touchHit(int touchIndex)`	Returns the number of times the touch point was initiated in this frame.
`mouse.touchUp(int touchIndex)`	Checks if the touch point at the given index was just released.
`mouse.touchX(int touchIndex)`	Gets the X-coordinate of the touch point at the given index.
`mouse.touchY(int touchIndex)`	Gets the Y-coordinate of the touch point at the given index.
Resource Manager (`resources`)
`resources.loadImage(String path, {int frameW, int frameH, ...})`	Loads an `Image` or `Images` (spritesheet) from a file.
`resources.loadFont(String path, double size, {bool antiAlias, ...})`	Loads a font file and generates a `BitmapFont` atlas.
`resources.loadSound(String path, {int retriggerDelayMs})`	Loads a `Sound` effect from an audio file.
`resources.loadString(String path)`	Asynchronously loads the content of a text file as a string.
Global Functions
`log(dynamic arg1, ...)`	General-purpose logging; can create/pop hierarchical log contexts.
`info(dynamic arg1, ...)`	Logs an informational message.
`warn(dynamic arg1, ...)`	Logs a warning message.
`error(dynamic arg1, ...)`	Logs an error message.
`die(dynamic arg1, ...)`	Logs a critical error and throws an exception.
`logReset()`	Clears the entire hierarchical log context stack.
`logOff()`	Disables all logging output.
`logOn()`	Enables logging output (clears any active filter).
`logEnableStacktrace(bool enable)`	Toggles the inclusion of a brief stack trace in log messages.
`logFilter([String? filter])`	Filters log messages based on a string; prefix with '!' for inverse filter.
`debugger()`	Programmatically triggers a breakpoint if a debugger is attached.
`nextPowerOfTwo(int value)`	Returns the smallest power of two greater than or equal to the input value.
`atan2Degree(num y, num x)`	Calculates the arc-tangent of y/x, returning the angle in degrees.
`sinDegree(num degrees)`	Calculates the sine of an angle provided in degrees.
`cosDegree(num degrees)`	Calculates the cosine of an angle provided in degrees.
`tanDegree(num degrees)`	Calculates the tangent of an angle provided in degrees.
`ColorFromInt(int value)`	Creates a `Color` (Vector4) from an integer (currently always returns white).
Extension Methods
`Images.isLoading`	(On `Images`) `true` if any image in the list is still loading.
`Images.textures`	(On `Images`) Returns a list of unique `Texture` objects from the images.
`Images.texture`	(On `Images`) Returns the `Texture` of the first image in the list.
`Images.dispose()`	(On `Images`) Disposes all images in the list.
`Images.pivotX = double value`	(On `Images`) Sets the horizontal pivot point for all images in the list.
`Images.pivotY = double value`	(On `Images`) Sets the vertical pivot point for all images in the list.
`Images.first`	(On `Images`) Gets the first `Image` in the list.
`Color.toUint8()`	(On `Color`/`Vector4`) Converts the RGBA color (0-1 range) to a packed int.
`List<num>.sum()`	Calculates the sum of all numbers in the list.
`List<num>.average()`	Calculates the average of all numbers in the list.
`int.has(int flag)`	Checks if a specific bit (flag) is set in the integer.
`int.hasAll(int flags)`	Checks if all specified bits (flags) are set in the integer.

Properties

dartDoc ↔ bool? Features Cheatsheet Getting Started My first App: This is just a unused variable to enforce the dart doc generator to include topics that aren't attached to a specific classes or functions. {@category Getting_Started} {@category TutorialFirstApp} {@category Features} {@category Cheatsheet}
getter/setter pair

Cheatsheet topic

Cheatsheet

Properties

bullseye2d package

Cheatsheet topic