I recreated the scrolling text box tutorial in my game. However, it is running a bit glitchy on mobile. For example, if I swipe up, the text first goes down for a second and then follows my finger up. You’ll see the problem if you open the tutorial on mobile. Any thoughts? I copied my code below.
var graphics = scene.make.graphics();
graphics.fillRect(x, y + 10, width, height - 20);
var mask = new Phaser.Display.Masks.GeometryMask(scene, graphics);
var text = scene.add.text(x + 20, y + 20, content, {
fontFamily: 'Assistant',
fontSize: '28px',
color: '#000000',
wordWrap: { width: width - 20 }
}).setOrigin(0);
text.setMask(mask);
var minY = height - text.height - 20;
if (text.height <= height - 20) {
minY = y + 20;
}
// The rectangle they can 'drag' within
var zone = scene.add.zone(x, y - 3, width, height + 6).setOrigin(0).setInteractive({useHandCursor: true});
zone.on('pointermove', function (pointer) {
if (pointer.isDown) {
text.y += (pointer.velocity.y / 10);
text.y = Phaser.Math.Clamp(text.y, minY, y + 20);
}
});
I had the same issue. My solution is using "pointer.y" instead of "pointer.velocity.y".
Here is my code:
var previousPointerPositionY;
var currentPointerPositionY;
zone.on('pointerdown', function (pointer) {
previousPointerPositionY = pointer.y;
});
zone.on('pointermove', function (pointer) {
if (pointer.isDown) {
currentPointerPositionY = pointer.y;
if(currentPointerPositionY > previousPointerPositionY){
text.y += 5;
} else if(currentPointerPositionY < previousPointerPositionY){
text.y -= 5;
}
previousPointerPositionY = currentPointerPositionY;
text.y = Phaser.Math.Clamp(text.y, -360, 150);
}
});
Related
Hi guys I been leanring WebGL and trying to make a Tetris game out of it.
I have a couple of questions I'd like to ask:
For this game I wanted to first draw the grid as the background. However I noticed that after I drew the line, if I use gl.clear(gl.COLOR_BUFFER_BIT ); after, it will clear all the lines I drew before. I understand that gl.clear(gl.COLOR_BUFFER_BIT ); is about clearing the color buffer (and you probably will ask why I would want to do that. Just bear with me. ). Then I tried use gl.uniform4f( uColor, 0, 0, 0, 1); to send the color again to the fragment shader but it doesn't help.
The snippet is like this
window.onload = function(){
getGLContext();
initShaders();
drawLines( 0, 0, 400,400 );
gl.clear(gl.COLOR_BUFFER_BIT );
gl.uniform4f( uColor, 0, 0, 0, 1);
}
For the game I need the grid as background and I need requestAnimationFrame for the game loop and will render Tetrominos inside the loop. Therefore after drawing the line I used this draw() to draw other Tetrominos. However it removes the line I drew before. And when I comment out gl.clear(gl.COLOR_BUFFER_BIT ); inside draw(), it will remove the line along with background color.
function draw() {
gl.clear(gl.COLOR_BUFFER_BIT );
gl.drawArrays(gl.TRIANGLES, 0, index*6);
requestAnimationFrame(draw);
}
Here is the demo: https://codepen.io/zhenghaohe/pen/LqxpjB
Hope you could answer these two questions. Thanks!
This is generally the way WebGL works.
WebGL is just draws into a rectangle of pixels. There is no memory of primitives. There is no structure. There is just code and the resulting canvas which is an rectangle of pixels.
Most WebGL programs/pages clear the entire canvas every frame and redraw 100% of the things they want to show every time they draw. For tetris the general code might be something like
function render() {
clear the canvas
draw the grid
draw all the stable pieces
draw the current piece
draw the next piece
draw the effects
draw the score
}
Any knowledge of primitives or other structure is entirely up to your code.
If you want the grid lines to be static then either set a static background with CSS or use another canvas
Using a background:
const gl = document.querySelector('#c').getContext('webgl');
function render(time) {
time *= 0.001;
gl.clearColor(0, 0, 0, 0);
gl.clear(gl.COLOR_BUFFER_BIT);
drawBlocks(gl, time);
requestAnimationFrame(render);
}
requestAnimationFrame(render);
// --- below this line not important to the answer
function drawBlocks(gl, time) {
gl.enable(gl.SCISSOR_TEST);
const numBlocks = 5;
for (let i = 0; i < numBlocks; ++i) {
const u = i / numBlocks;
gl.clearColor(i / 5, i / 2 % 1, i / 3 % 1, 1);
const x = 150 + Math.sin(time + u * Math.PI * 2) * 130;
const y = 75 + Math.cos(time + u * Math.PI * 2) * 55;
gl.scissor(x, y, 20, 20);
gl.clear(gl.COLOR_BUFFER_BIT);
}
gl.disable(gl.SCISSOR_TEST);
}
#c {
background-image: url(https://i.imgur.com/ZCfccZh.png);
}
<canvas id="c"></canvas>
Using 2 canvases
// this is the context for the back canvas. It could also be webgl
// using a 2D context just to make the sample simpler
const ctx = document.querySelector('#back').getContext('2d');
drawGrid(ctx);
// this is the context for the front canvas
const gl = document.querySelector('#front').getContext('webgl');
function render(time) {
time *= 0.001;
gl.clearColor(0, 0, 0, 0);
gl.clear(gl.COLOR_BUFFER_BIT);
drawBlocks(gl, time);
requestAnimationFrame(render);
}
requestAnimationFrame(render);
// --- below this line not important to the answer
function drawBlocks(gl, time) {
gl.enable(gl.SCISSOR_TEST);
const numBlocks = 5;
for (let i = 0; i < numBlocks; ++i) {
const u = i / numBlocks;
gl.clearColor(i / 5, i / 2 % 1, i / 3 % 1, 1);
const x = 150 + Math.sin(time + u * Math.PI * 2) * 130;
const y = 75 + Math.cos(time + u * Math.PI * 2) * 55;
gl.scissor(x, y, 20, 20);
gl.clear(gl.COLOR_BUFFER_BIT);
}
gl.disable(gl.SCISSOR_TEST);
}
function drawGrid(ctx) {
// draw grid
ctx.translate(-10.5, -5.5);
ctx.beginPath();
for (let i = 0; i < 330; i += 20) {
ctx.moveTo(0, i);
ctx.lineTo(330, i);
ctx.moveTo(i, 0);
ctx.lineTo(i, 300);
}
ctx.strokeStyle = "blue";
ctx.stroke();
}
#container {
position: relative; /* required so we can position child elements */
}
#front {
position: absolute;
left: 0;
top: 0;
}
<div id="container">
<canvas id="back"></canvas>
<canvas id="front"></canvas>
</div>
As for why it clears even if you didn't call clear that's because that's whqt the spec says it's supposed to do
See: Why WebGL 'clear' draw to front buffer?
Looking to change the color of my tooltip but not having much success. Is this a simple need for a color onto the dojo.style command? Here is my code so far
// create node for the tooltip
var tip = "Click on problem location";
var tooltip = dojo.create("div", { "class": "tooltip", "innerHTML": tip }, map.container);
dojo.style(tooltip, "position", "fixed");
// update the tooltip as the mouse moves over the map
dojo.connect(map, "onMouseMove", function(evt) {
var px, py;
if (evt.clientX || evt.pageY) {
px = evt.clientX;
py = evt.clientY;
} else {
px = evt.clientX + dojo.body().scrollLeft - dojo.body().clientLeft;
py = evt.clientY + dojo.body().scrollTop - dojo.body().clientTop;
}
// dojo.style(tooltip, "display", "none");
tooltip.style.display = "none";
dojo.style(tooltip, { left: (px + 15) + "px", top: (py) + "px" });
// dojo.style(tooltip, "display", "");
tooltip.style.display = "";
// console.log("updated tooltip pos.");
});
// hide the tooltip the cursor isn't over the map
dojo.connect(map, "onMouseOut", function(evt){
tooltip.style.display = "none";
});
I have a canvas, which is infinite right now, I can make PAN up to the coordinates that I want. But our users, are lost after an intense use of it, because they can not find the objects.
I want to implement a limit that the user puts in the canvas.
I know how to limit the bread when, the work size is smaller than the size of the canvas, simply not letting the bread tool do its job.
But I have problems when the user asks me for a bread size larger than the size of the canvas
The default canvas size is 900 x 600, and my user needs to be able to work on 2000x2000. The canvas would still be 900x600 but the PAN tool is enabled, and can move within the canvas, up to the 2000x2000 limit
I have seen in the fabric demos, that there is a tutorial of Pan, but it is not compatible with my problem, because in that example, the canvas is fixed
I have solved my problem with the following code
var maxWidth = 1000;
var maxHeight = 1000:
if(obj.currentHeight > maxHeight || obj.currentWidth > maxHeight){
return;
}
obj.setCoords();
// top-left corner
if(obj.getBoundingRect(true).top < 0 || obj.getBoundingRect(true).left < 0){
obj.top = Math.max(obj.top, obj.top-obj.getBoundingRect(true).top)+5;
obj.left = Math.max(obj.left, obj.left-obj.getBoundingRect(true).left)+5;
}
// bot-right corner
if(obj.getBoundingRect(true).top+obj.getBoundingRect(true).height > maxHeight || obj.getBoundingRect(true).left+obj.getBoundingRect(true).width > maxWidth){
obj.top = Math.min(obj.top, (maxHeight-5)-obj.getBoundingRect(true).height+obj.top-obj.getBoundingRect(true).top);
obj.left = Math.min(obj.left, (maxWidth-5)-obj.getBoundingRect(true).width+obj.left-obj.getBoundingRect(true).left);
}
canvas.on('mouse:down', function(e){
var evt = e.e
this.lastPosX = evt.clientX;
this.lastPosY = evt.clientY;
});
canvas.on('mouse:move', function (e) {
if (global_panning && e && e.e && global_mover) {
zoom = canvas.getZoom();
if(zoom<0.4){
this.viewportTransform[4] = 200 - maxWidth * zoom /2;
this.viewportTransform[5] = 200 - maxHeight * zoom /2;
}else{
this.viewportTransform[4] += e.e.clientX - this.lastPosX;
this.viewportTransform[5] += e.e.clientY - this.lastPosY;
if (this.viewportTransform[4] >= 0) {
this.viewportTransform[4] = 0;
} else if (this.viewportTransform[4] < canvas.getWidth() - maxWidth * zoom) {
this.viewportTransform[4] = canvas.getWidth() - maxWidth * zoom;
}
if (this.viewportTransform[5] >= 0) {
this.viewportTransform[5] = 0;
} else if (this.viewportTransform[5] < canvas.getHeight() - maxHeight *zoom) {
this.viewportTransform[5] = canvas.getHeight() - maxHeight * zoom;
}
//console.log(this.viewportTransform);
}
this.requestRenderAll();
this.lastPosX = e.e.clientX;
this.lastPosY = e.e.clientY;
}
});
In fabricJS I have used the code that comes in the demos of Zoom, in tutorial 5, customizing it to my needs. In my case, the size of the limit is decided by the user, so I have defined a variable, which collects that value, and replace the value of the size of the canvas that is in the FabricJS instance for mine.
I hope this can help you in the future, who needs help with this topic
I'm building an app that can design your own business card. I have to add an object to two canvases in a single click. Here are my codes:
$('#image-list').on('click','.image-option',function(e) {
var el = e.target;
/*temp code*/
var offset = 50;
var left = fabric.util.getRandomInt(0 + offset, 200 - offset);
var top = fabric.util.getRandomInt(0 + offset, 400 - offset);
var angle = fabric.util.getRandomInt(-20, 40);
var width = fabric.util.getRandomInt(30, 50);
var opacity = (function(min, max){ return Math.random() * (max - min) + min; })(0.5, 1);
var canvasObject;
// if ($('#flip').attr('data-facing') === 'front') {
// canvasObject = canvas;
// } else {
// canvasObject = canvas2;
// }
fabric.Image.fromURL(el.src, function(image) {
image.set({
left: left,
top: top,
angle: 0,
padding: 10,
cornersize: 10,
hasRotatingPoint:true
});
canvas.add(image);
canvas2.add(image);
});
})
The problem is, when I resized or move the image on the 'front canvas', it also renders the same way in the 'back canvas'. In my case, I don't want the object to be that way. So is there a way to prevent the obect 'mirroring' on the other canvas? Thanks.
You cannot add the same object to 2 canvases.
You have to create 2 objects.
Also take note that if you have an html image element on your page you do not need to load it from URL again. Is already loaded, so pass the image element to the constructor directly
$('#image-list').on('click','.image-option',function(e) {
var el = e.target;
/*temp code*/
var offset = 50;
var left = fabric.util.getRandomInt(0 + offset, 200 - offset);
var top = fabric.util.getRandomInt(0 + offset, 400 - offset);
var angle = fabric.util.getRandomInt(-20, 40);
var width = fabric.util.getRandomInt(30, 50);
var opacity = (function(min, max){ return Math.random() * (max - min) + min; })(0.5, 1);
var canvasObject;
// if ($('#flip').attr('data-facing') === 'front') {
// canvasObject = canvas;
// } else {
// canvasObject = canvas2;
// }
image = new fabric.Image(el, {
left: left,
top: top,
angle: 0,
padding: 10,
cornersize: 10,
hasRotatingPoint:true
});
image2 = new fabric.Image(el, {
left: left,
top: top,
angle: 0,
padding: 10,
cornersize: 10,
hasRotatingPoint:true
});
canvas.add(image);
canvas2.add(image2);
});
})
I have an algorithm for Floodfilling a canvas. Im trying to incorporate this with fabricJS. So here is the dilemna.... I create a fabric.Canvas(). Which creates a wrapper canvas and also an upper-canvas canvas. I click on the canvas to apply my Floodfill(). This works fine and applies my color. But as soon as i go to drag my canvas objects around, or add additional objects to the canvas, the color disappears and looks like it resets of sort.
Any idea why this is?
This happen because fabricjs wipe out all canvas every frame and redraw from its internal data.
I made a JSfiddle that implements Flood Fill for Fabric JS. Check it here: https://jsfiddle.net/av01d/dfvp9j2u/
/*
* FloodFill for fabric.js
* #author Arjan Haverkamp (av01d)
* #date October 2018
*/
var FloodFill = {
// Compare subsection of array1's values to array2's values, with an optional tolerance
withinTolerance: function(array1, offset, array2, tolerance)
{
var length = array2.length,
start = offset + length;
tolerance = tolerance || 0;
// Iterate (in reverse) the items being compared in each array, checking their values are
// within tolerance of each other
while(start-- && length--) {
if(Math.abs(array1[start] - array2[length]) > tolerance) {
return false;
}
}
return true;
},
// The actual flood fill implementation
fill: function(imageData, getPointOffsetFn, point, color, target, tolerance, width, height)
{
var directions = [[1, 0], [0, 1], [0, -1], [-1, 0]],
coords = [],
points = [point],
seen = {},
key,
x,
y,
offset,
i,
x2,
y2,
minX = -1,
maxX = -1,
minY = -1,
maxY = -1;
// Keep going while we have points to walk
while (!!(point = points.pop())) {
x = point.x;
y = point.y;
offset = getPointOffsetFn(x, y);
// Move to next point if this pixel isn't within tolerance of the color being filled
if (!FloodFill.withinTolerance(imageData, offset, target, tolerance)) {
continue;
}
if (x > maxX) { maxX = x; }
if (y > maxY) { maxY = y; }
if (x < minX || minX == -1) { minX = x; }
if (y < minY || minY == -1) { minY = y; }
// Update the pixel to the fill color and add neighbours onto stack to traverse
// the fill area
i = directions.length;
while (i--) {
// Use the same loop for setting RGBA as for checking the neighbouring pixels
if (i < 4) {
imageData[offset + i] = color[i];
coords[offset+i] = color[i];
}
// Get the new coordinate by adjusting x and y based on current step
x2 = x + directions[i][0];
y2 = y + directions[i][1];
key = x2 + ',' + y2;
// If new coordinate is out of bounds, or we've already added it, then skip to
// trying the next neighbour without adding this one
if (x2 < 0 || y2 < 0 || x2 >= width || y2 >= height || seen[key]) {
continue;
}
// Push neighbour onto points array to be processed, and tag as seen
points.push({ x: x2, y: y2 });
seen[key] = true;
}
}
return {
x: minX,
y: minY,
width: maxX-minX,
height: maxY-minY,
coords: coords
}
}
}; // End FloodFill
var fcanvas; // Fabric Canvas
var fillColor = '#f00';
var fillTolerance = 2;
function hexToRgb(hex, opacity) {
opacity = Math.round(opacity * 255) || 255;
hex = hex.replace('#', '');
var rgb = [], re = new RegExp('(.{' + hex.length/3 + '})', 'g');
hex.match(re).map(function(l) {
rgb.push(parseInt(hex.length % 2 ? l+l : l, 16));
});
return rgb.concat(opacity);
}
function floodFill(enable) {
if (!enable) {
fcanvas.off('mouse:down');
fcanvas.selection = true;
fcanvas.forEachObject(function(object){
object.selectable = true;
});
return;
}
fcanvas.deactivateAll().renderAll(); // Hide object handles!
fcanvas.selection = false;
fcanvas.forEachObject(function(object){
object.selectable = false;
});
fcanvas.on({
'mouse:down': function(e) {
var mouse = fcanvas.getPointer(e.e),
mouseX = Math.round(mouse.x), mouseY = Math.round(mouse.y),
canvas = fcanvas.lowerCanvasEl,
context = canvas.getContext('2d'),
parsedColor = hexToRgb(fillColor),
imageData = context.getImageData(0, 0, canvas.width, canvas.height),
getPointOffset = function(x,y) {
return 4 * (y * imageData.width + x)
},
targetOffset = getPointOffset(mouseX, mouseY),
target = imageData.data.slice(targetOffset, targetOffset + 4);
if (FloodFill.withinTolerance(target, 0, parsedColor, fillTolerance)) {
// Trying to fill something which is (essentially) the fill color
console.log('Ignore... same color')
return;
}
// Perform flood fill
var data = FloodFill.fill(
imageData.data,
getPointOffset,
{ x: mouseX, y: mouseY },
parsedColor,
target,
fillTolerance,
imageData.width,
imageData.height
);
if (0 == data.width || 0 == data.height) {
return;
}
var tmpCanvas = document.createElement('canvas'), tmpCtx = tmpCanvas.getContext('2d');
tmpCanvas.width = canvas.width;
tmpCanvas.height = canvas.height;
var palette = tmpCtx.getImageData(0, 0, tmpCanvas.width, tmpCanvas.height); // x, y, w, h
palette.data.set(new Uint8ClampedArray(data.coords)); // Assuming values 0..255, RGBA
tmpCtx.putImageData(palette, 0, 0); // Repost the data.
var imgData = tmpCtx.getImageData(data.x, data.y, data.width, data.height); // Get cropped image
tmpCanvas.width = data.width;
tmpCanvas.height = data.height;
tmpCtx.putImageData(imgData,0,0);
fcanvas.add(new fabric.Image(tmpCanvas, {
left: data.x,
top: data.y,
selectable: false
}))
}
});
}
$(function() {
// Init Fabric Canvas:
fcanvas = new fabric.Canvas('c', {
backgroundColor:'#fff',
enableRetinaScaling: false
});
// Add some demo-shapes:
fcanvas.add(new fabric.Circle({
radius: 80,
fill: false,
left: 100,
top: 100,
stroke: '#000',
strokeWidth: 2
}));
fcanvas.add(new fabric.Triangle({
width: 120,
height: 160,
left: 50,
top: 50,
stroke: '#000',
fill: '#00f',
strokeWidth: 2
}));
fcanvas.add(new fabric.Rect({
width: 120,
height: 160,
left: 150,
top: 50,
fill: 'red',
stroke: '#000',
strokeWidth: 2
}));
fcanvas.add(new fabric.Rect({
width: 200,
height: 120,
left: 200,
top: 120,
fill: 'green',
stroke: '#000',
strokeWidth: 2
}));
/* Images work very well too. Make sure they're CORS
enabled though! */
var img = new Image();
img.crossOrigin = 'anonymous';
img.onload = function() {
fcanvas.add(new fabric.Image(img, {
left: 300,
top: 100,
angle: 30,
}));
}
img.src = 'http://misc.avoid.org/chip.png';
});