littlejsengine
Version:
LittleJS - Tiny and Fast HTML5 Game Engine
470 lines (419 loc) • 16.6 kB
JavaScript
/**
* LittleJS Debug System
* - Press Esc to show debug overlay with mouse pick
* - Number keys toggle debug functions
* - +/- apply time scale
* - Debug primitive rendering
* - Save a 2d canvas as a png image
* @namespace Debug
*/
;
/** True if debug is enabled
* @type {boolean}
* @default
* @memberof Debug */
const debug = true;
/** True if asserts are enabled
* @type {boolean}
* @default
* @memberof Debug */
const enableAsserts = true;
/** Size to render debug points by default
* @type {number}
* @default
* @memberof Debug */
const debugPointSize = .5;
/** True if watermark with FPS should be shown, false in release builds
* @type {boolean}
* @default
* @memberof Debug */
let showWatermark = true;
/** Key code used to toggle debug mode, Esc by default
* @type {string}
* @default
* @memberof Debug */
let debugKey = 'Escape';
/** True if the debug overlay is active, always false in release builds
* @type {boolean}
* @default
* @memberof Debug */
let debugOverlay = false;
// Engine internal variables not exposed to documentation
let debugPrimitives = [], debugPhysics = false, debugRaycast = false, debugParticles = false, debugGamepads = false, debugMedals = false, debugTakeScreenshot, downloadLink;
///////////////////////////////////////////////////////////////////////////////
// Debug helper functions
/** Asserts if the expression is false, does not do anything in release builds
* @param {boolean} assert
* @param {Object} [output]
* @memberof Debug */
function ASSERT(assert, output)
{
if (enableAsserts)
output ? console.assert(assert, output) : console.assert(assert);
}
/** Draw a debug rectangle in world space
* @param {Vector2} pos
* @param {Vector2} [size=Vector2()]
* @param {string} [color]
* @param {number} [time]
* @param {number} [angle]
* @param {boolean} [fill]
* @memberof Debug */
function debugRect(pos, size=vec2(), color='#fff', time=0, angle=0, fill=false)
{
ASSERT(typeof color == 'string', 'pass in css color strings');
debugPrimitives.push({pos, size:vec2(size), color, time:new Timer(time), angle, fill});
}
/** Draw a debug poly in world space
* @param {Vector2} pos
* @param {Array<Vector2>} points
* @param {string} [color]
* @param {number} [time]
* @param {number} [angle]
* @param {boolean} [fill]
* @memberof Debug */
function debugPoly(pos, points, color='#fff', time=0, angle=0, fill=false)
{
ASSERT(typeof color == 'string', 'pass in css color strings');
debugPrimitives.push({pos, points, color, time:new Timer(time), angle, fill});
}
/** Draw a debug circle in world space
* @param {Vector2} pos
* @param {number} [radius]
* @param {string} [color]
* @param {number} [time]
* @param {boolean} [fill]
* @memberof Debug */
function debugCircle(pos, radius=0, color='#fff', time=0, fill=false)
{
ASSERT(typeof color == 'string', 'pass in css color strings');
debugPrimitives.push({pos, size:radius, color, time:new Timer(time), angle:0, fill});
}
/** Draw a debug point in world space
* @param {Vector2} pos
* @param {string} [color]
* @param {number} [time]
* @param {number} [angle]
* @memberof Debug */
function debugPoint(pos, color, time, angle)
{
ASSERT(typeof color == 'string', 'pass in css color strings');
debugRect(pos, undefined, color, time, angle);
}
/** Draw a debug line in world space
* @param {Vector2} posA
* @param {Vector2} posB
* @param {string} [color]
* @param {number} [thickness]
* @param {number} [time]
* @memberof Debug */
function debugLine(posA, posB, color, thickness=.1, time)
{
const halfDelta = vec2((posB.x - posA.x)/2, (posB.y - posA.y)/2);
const size = vec2(thickness, halfDelta.length()*2);
debugRect(posA.add(halfDelta), size, color, time, halfDelta.angle(), true);
}
/** Draw a debug combined axis aligned bounding box in world space
* @param {Vector2} pA - position A
* @param {Vector2} sA - size A
* @param {Vector2} pB - position B
* @param {Vector2} sB - size B
* @param {string} [color]
* @memberof Debug */
function debugOverlap(pA, sA, pB, sB, color)
{
const minPos = vec2(min(pA.x - sA.x/2, pB.x - sB.x/2), min(pA.y - sA.y/2, pB.y - sB.y/2));
const maxPos = vec2(max(pA.x + sA.x/2, pB.x + sB.x/2), max(pA.y + sA.y/2, pB.y + sB.y/2));
debugRect(minPos.lerp(maxPos,.5), maxPos.subtract(minPos), color);
}
/** Draw a debug axis aligned bounding box in world space
* @param {string} text
* @param {Vector2} pos
* @param {number} [size]
* @param {string} [color]
* @param {number} [time]
* @param {number} [angle]
* @param {string} [font]
* @memberof Debug */
function debugText(text, pos, size=1, color='#fff', time=0, angle=0, font='monospace')
{
ASSERT(typeof color == 'string', 'pass in css color strings');
debugPrimitives.push({text, pos, size, color, time:new Timer(time), angle, font});
}
/** Clear all debug primitives in the list
* @memberof Debug */
function debugClear() { debugPrimitives = []; }
/** Trigger debug system to take a screenshot
* @memberof Debug */
function debugScreenshot() { debugTakeScreenshot = 1; }
/** Save a canvas to disk
* @param {HTMLCanvasElement} canvas
* @param {string} [filename]
* @param {string} [type]
* @memberof Debug */
function debugSaveCanvas(canvas, filename='screenshot', type='image/png')
{ debugSaveDataURL(canvas.toDataURL(type), filename); }
/** Save a text file to disk
* @param {string} text
* @param {string} [filename]
* @param {string} [type]
* @memberof Debug */
function debugSaveText(text, filename='text', type='text/plain')
{ debugSaveDataURL(URL.createObjectURL(new Blob([text], {'type':type})), filename); }
/** Save a data url to disk
* @param {string} dataURL
* @param {string} filename
* @memberof Debug */
function debugSaveDataURL(dataURL, filename)
{
downloadLink.download = filename;
downloadLink.href = dataURL;
downloadLink.click();
}
/** Show error as full page of red text
* @memberof Debug */
function debugShowErrors()
{
onunhandledrejection = (event)=>showError(event.reason);
onerror = (event, source, lineno, colno)=>
showError(`${event}\n${source}\nLn ${lineno}, Col ${colno}`);
const showError = (message)=>
{
// replace entire page with error message
document.body.style.display = '';
document.body.style.backgroundColor = '#111';
document.body.innerHTML = `<pre style=color:#f00;font-size:50px>` + message;
}
}
///////////////////////////////////////////////////////////////////////////////
// Engine debug functions (called automatically)
function debugInit()
{
// create link for saving screenshots
downloadLink = document.createElement('a');
}
function debugUpdate()
{
if (!debug)
return;
if (keyWasPressed(debugKey)) // Esc
debugOverlay = !debugOverlay;
if (debugOverlay)
{
if (keyWasPressed('Digit0'))
showWatermark = !showWatermark;
if (keyWasPressed('Digit1'))
debugPhysics = !debugPhysics, debugParticles = false;
if (keyWasPressed('Digit2'))
debugParticles = !debugParticles, debugPhysics = false;
if (keyWasPressed('Digit3'))
debugGamepads = !debugGamepads;
if (keyWasPressed('Digit4'))
debugRaycast = !debugRaycast;
if (keyWasPressed('Digit5'))
debugScreenshot();
}
}
function debugRender()
{
glCopyToContext(mainContext);
if (debugTakeScreenshot)
{
// combine canvases, remove alpha and save
combineCanvases();
const w = mainCanvas.width, h = mainCanvas.height;
overlayContext.fillRect(0,0,w,h);
overlayContext.drawImage(mainCanvas, 0, 0);
debugSaveCanvas(overlayCanvas);
debugTakeScreenshot = 0;
}
if (debugGamepads && gamepadsEnable && navigator.getGamepads)
{
// gamepad debug display
const gamepads = navigator.getGamepads();
for (let i = gamepads.length; i--;)
{
const gamepad = gamepads[i];
if (gamepad)
{
const stickScale = 1;
const buttonScale = .2;
const centerPos = cameraPos;
const sticks = gamepadStickData[i];
for (let j = sticks.length; j--;)
{
const drawPos = centerPos.add(vec2(j*stickScale*2, i*stickScale*3));
const stickPos = drawPos.add(sticks[j].scale(stickScale));
debugCircle(drawPos, stickScale, '#fff7',0,true);
debugLine(drawPos, stickPos, '#f00');
debugPoint(stickPos, '#f00');
}
for (let j = gamepad.buttons.length; j--;)
{
const drawPos = centerPos.add(vec2(j*buttonScale*2, i*stickScale*3-stickScale-buttonScale));
const pressed = gamepad.buttons[j].pressed;
debugCircle(drawPos, buttonScale, pressed ? '#f00' : '#fff7', 0, true);
debugText(''+j, drawPos, .2);
}
}
}
}
let debugObject;
if (debugOverlay)
{
const saveContext = mainContext;
mainContext = overlayContext;
// draw red rectangle around screen
const cameraSize = getCameraSize();
debugRect(cameraPos, cameraSize.subtract(vec2(.1)), '#f008');
// mouse pick
let bestDistance = Infinity;
for (const o of engineObjects)
{
if (o.destroyed)
continue;
if (o instanceof TileLayer)
continue; // prevent tile layers from being picked
o.renderDebugInfo();
if (!o.size.x || !o.size.y)
continue;
const distance = mousePos.distanceSquared(o.pos);
if (distance < bestDistance)
{
bestDistance = distance;
debugObject = o;
}
}
if (tileCollisionSize.x > 0 && tileCollisionSize.y > 0)
drawRect(mousePos.floor().add(vec2(.5)), vec2(1), rgb(0,0,1,.5), 0, false);
mainContext = saveContext;
//glCopyToContext(mainContext = saveContext);
}
{
// draw debug primitives
overlayContext.lineWidth = 2;
const pointSize = debugPointSize * cameraScale;
debugPrimitives.forEach(p=>
{
overlayContext.save();
// create canvas transform from world space to screen space
const pos = worldToScreen(p.pos);
overlayContext.translate(pos.x|0, pos.y|0);
overlayContext.rotate(p.angle);
overlayContext.scale(1, p.text ? 1 : -1);
overlayContext.fillStyle = overlayContext.strokeStyle = p.color;
if (p.text != undefined)
{
overlayContext.font = p.size*cameraScale + 'px '+ p.font;
overlayContext.textAlign = 'center';
overlayContext.textBaseline = 'middle';
overlayContext.fillText(p.text, 0, 0);
}
else if (p.points != undefined)
{
// poly
overlayContext.beginPath();
for (const point of p.points)
{
const p2 = point.scale(cameraScale).floor();
overlayContext.lineTo(p2.x, p2.y);
}
overlayContext.closePath();
p.fill && overlayContext.fill();
overlayContext.stroke();
}
else if (p.size == 0 || p.size.x === 0 && p.size.y === 0)
{
// point
overlayContext.fillRect(-pointSize/2, -1, pointSize, 3);
overlayContext.fillRect(-1, -pointSize/2, 3, pointSize);
}
else if (p.size.x != undefined)
{
// rect
const s = p.size.scale(cameraScale).floor();
const w = s.x, h = s.y;
p.fill && overlayContext.fillRect(-w/2|0, -h/2|0, w, h);
overlayContext.strokeRect(-w/2|0, -h/2|0, w, h);
}
else
{
// circle
overlayContext.beginPath();
overlayContext.arc(0, 0, p.size*cameraScale, 0, 9);
p.fill && overlayContext.fill();
overlayContext.stroke();
}
overlayContext.restore();
});
// remove expired primitives
debugPrimitives = debugPrimitives.filter(r=>r.time<0);
}
if (debugObject)
{
const saveContext = mainContext;
mainContext = overlayContext;
const raycastHitPos = tileCollisionRaycast(debugObject.pos, mousePos);
raycastHitPos && drawRect(raycastHitPos.floor().add(vec2(.5)), vec2(1), rgb(0,1,1,.3));
drawLine(mousePos, debugObject.pos, .1, raycastHitPos ? rgb(1,0,0,.5) : rgb(0,1,0,.5), false);
const debugText = 'mouse pos = ' + mousePos +
'\nmouse collision = ' + getTileCollisionData(mousePos) +
'\n\n--- object info ---\n' +
debugObject.toString();
drawTextScreen(debugText, mousePosScreen, 24, rgb(), .05, undefined, 'center', 'monospace');
mainContext = saveContext;
}
{
// draw debug overlay
overlayContext.save();
overlayContext.fillStyle = '#fff';
overlayContext.textAlign = 'left';
overlayContext.textBaseline = 'top';
overlayContext.font = '28px monospace';
overlayContext.shadowColor = '#000';
overlayContext.shadowBlur = 9;
let x = 9, y = -20, h = 30;
if (debugOverlay)
{
overlayContext.fillText(engineName, x, y += h);
overlayContext.fillText('Objects: ' + engineObjects.length, x, y += h);
overlayContext.fillText('Time: ' + formatTime(time), x, y += h);
overlayContext.fillText('---------', x, y += h);
overlayContext.fillStyle = '#f00';
overlayContext.fillText('ESC: Debug Overlay', x, y += h);
overlayContext.fillStyle = debugPhysics ? '#f00' : '#fff';
overlayContext.fillText('1: Debug Physics', x, y += h);
overlayContext.fillStyle = debugParticles ? '#f00' : '#fff';
overlayContext.fillText('2: Debug Particles', x, y += h);
overlayContext.fillStyle = debugGamepads ? '#f00' : '#fff';
overlayContext.fillText('3: Debug Gamepads', x, y += h);
overlayContext.fillStyle = debugRaycast ? '#f00' : '#fff';
overlayContext.fillText('4: Debug Raycasts', x, y += h);
overlayContext.fillStyle = '#fff';
overlayContext.fillText('5: Save Screenshot', x, y += h);
let keysPressed = '';
for(const i in inputData[0])
{
if (keyIsDown(i, 0))
keysPressed += i + ' ' ;
}
keysPressed && overlayContext.fillText('Keys Down: ' + keysPressed, x, y += h);
let buttonsPressed = '';
if (inputData[1])
for(const i in inputData[1])
{
if (keyIsDown(i, 1))
buttonsPressed += i + ' ' ;
}
buttonsPressed && overlayContext.fillText('Gamepad: ' + buttonsPressed, x, y += h);
}
else
{
overlayContext.fillText(debugPhysics ? 'Debug Physics' : '', x, y += h);
overlayContext.fillText(debugParticles ? 'Debug Particles' : '', x, y += h);
overlayContext.fillText(debugRaycast ? 'Debug Raycasts' : '', x, y += h);
overlayContext.fillText(debugGamepads ? 'Debug Gamepads' : '', x, y += h);
}
overlayContext.restore();
}
}