;(function(undefined) {
'use strict';
if (typeof sigma === 'undefined')
throw 'sigma is not declared';
var _root = this;
// Initialize packages:
sigma.utils = sigma.utils || {};
/**
* MISC UTILS:
*/
/**
* This function takes any number of objects as arguments, copies from each
* of these objects each pair key/value into a new object, and finally
* returns this object.
*
* The arguments are parsed from the last one to the first one, such that
* when several objects have keys in common, the "earliest" object wins.
*
* Example:
* ********
* > var o1 = {
* > a: 1,
* > b: 2,
* > c: '3'
* > },
* > o2 = {
* > c: '4',
* > d: [ 5 ]
* > };
* > sigma.utils.extend(o1, o2);
* > // Returns: {
* > // a: 1,
* > // b: 2,
* > // c: '3',
* > // d: [ 5 ]
* > // };
*
* @param {object+} Any number of objects.
* @return {object} The merged object.
*/
sigma.utils.extend = function() {
var i,
k,
res = {},
l = arguments.length;
for (i = l - 1; i >= 0; i--)
for (k in arguments[i])
res[k] = arguments[i][k];
return res;
};
/**
* A short "Date.now()" polyfill.
*
* @return {Number} The current time (in ms).
*/
sigma.utils.dateNow = function() {
return Date.now ? Date.now() : new Date().getTime();
};
/**
* Takes a package name as parameter and checks at each lebel if it exists,
* and if it does not, creates it.
*
* Example:
* ********
* > sigma.utils.pkg('a.b.c');
* > a.b.c;
* > // Object {};
* >
* > sigma.utils.pkg('a.b.d');
* > a.b;
* > // Object { c: {}, d: {} };
*
* @param {string} pkgName The name of the package to create/find.
* @return {object} The related package.
*/
sigma.utils.pkg = function(pkgName) {
return (pkgName || '').split('.').reduce(function(context, objName) {
return (objName in context) ?
context[objName] :
(context[objName] = {});
}, _root);
};
/**
* Returns a unique incremental number ID.
*
* Example:
* ********
* > sigma.utils.id();
* > // 1;
* >
* > sigma.utils.id();
* > // 2;
* >
* > sigma.utils.id();
* > // 3;
*
* @param {string} pkgName The name of the package to create/find.
* @return {object} The related package.
*/
sigma.utils.id = (function() {
var i = 0;
return function() {
return ++i;
};
})();
/**
* This function takes an hexa color (for instance "#ffcc00" or "#fc0") or a
* rgb / rgba color (like "rgb(255,255,12)" or "rgba(255,255,12,1)") and
* returns an integer equal to "r * 255 * 255 + g * 255 + b", to gain some
* memory in the data given to WebGL shaders.
*
* Note that the function actually caches its results for better performance.
*
* @param {string} val The hexa or rgba color.
* @return {number} The number value.
*/
var floatColorCache = {};
sigma.utils.floatColor = function(val) {
// Is the color already computed?
if (floatColorCache[val])
return floatColorCache[val];
var original = val,
r = 0,
g = 0,
b = 0;
if (val[0] === '#') {
val = val.slice(1);
if (val.length === 3) {
r = parseInt(val.charAt(0) + val.charAt(0), 16);
g = parseInt(val.charAt(1) + val.charAt(1), 16);
b = parseInt(val.charAt(2) + val.charAt(2), 16);
}
else {
r = parseInt(val.charAt(0) + val.charAt(1), 16);
g = parseInt(val.charAt(2) + val.charAt(3), 16);
b = parseInt(val.charAt(4) + val.charAt(5), 16);
}
} else if (val.match(/^ *rgba? *\(/)) {
val = val.match(
/^ *rgba? *\( *([0-9]*) *, *([0-9]*) *, *([0-9]*) *(,.*)?\) *$/
);
r = +val[1];
g = +val[2];
b = +val[3];
}
var color = (
r * 256 * 256 +
g * 256 +
b
);
// Caching the color
floatColorCache[original] = color;
return color;
};
/**
* Perform a zoom into a camera, with or without animation, to the
* coordinates indicated using a specified ratio.
*
* Recognized parameters:
* **********************
* Here is the exhaustive list of every accepted parameters in the animation
* object:
*
* {?number} duration An amount of time that means the duration of the
* animation. If this parameter doesn't exist the
* zoom will be performed without animation.
* {?function} onComplete A function to perform it after the animation. It
* will be performed even if there is no duration.
*
* @param {camera} The camera where perform the zoom.
* @param {x} The X coordiantion where the zoom goes.
* @param {y} The Y coordiantion where the zoom goes.
* @param {ratio} The ratio to apply it to the current camera ratio.
* @param {?animation} A dictionary with options for a possible animation.
*/
sigma.utils.zoomTo = function(camera, x, y, ratio, animation) {
var settings = camera.settings,
count,
newRatio,
animationSettings,
coordinates;
// Create the newRatio dealing with min / max:
newRatio = Math.max(
settings('zoomMin'),
Math.min(
settings('zoomMax'),
camera.ratio * ratio
)
);
// Check that the new ratio is different from the initial one:
if (newRatio !== camera.ratio) {
// Create the coordinates variable:
ratio = newRatio / camera.ratio;
coordinates = {
x: x * (1 - ratio) + camera.x,
y: y * (1 - ratio) + camera.y,
ratio: newRatio
};
if (animation && animation.duration) {
// Complete the animation setings:
count = sigma.misc.animation.killAll(camera);
animation = sigma.utils.extend(
animation,
{
easing: count ? 'quadraticOut' : 'quadraticInOut'
}
);
sigma.misc.animation.camera(camera, coordinates, animation);
} else {
camera.goTo(coordinates);
if (animation && animation.onComplete)
animation.onComplete();
}
}
};
/**
* Return the control point coordinates for a quadratic bezier curve.
*
* @param {number} x1 The X coordinate of the start point.
* @param {number} y1 The Y coordinate of the start point.
* @param {number} x2 The X coordinate of the end point.
* @param {number} y2 The Y coordinate of the end point.
* @return {x,y} The control point coordinates.
*/
sigma.utils.getQuadraticControlPoint = function(x1, y1, x2, y2) {
return {
x: (x1 + x2) / 2 + (y2 - y1) / 4,
y: (y1 + y2) / 2 + (x1 - x2) / 4
};
};
/**
* Compute the coordinates of the point positioned
* at length t in the quadratic bezier curve.
*
* @param {number} t In [0,1] the step percentage to reach
* the point in the curve from the context point.
* @param {number} x1 The X coordinate of the context point.
* @param {number} y1 The Y coordinate of the context point.
* @param {number} x2 The X coordinate of the ending point.
* @param {number} y2 The Y coordinate of the ending point.
* @param {number} xi The X coordinate of the control point.
* @param {number} yi The Y coordinate of the control point.
* @return {object} {x,y}.
*/
sigma.utils.getPointOnQuadraticCurve = function(t, x1, y1, x2, y2, xi, yi) {
// http://stackoverflow.com/a/5634528
return {
x: Math.pow(1 - t, 2) * x1 + 2 * (1 - t) * t * xi + Math.pow(t, 2) * x2,
y: Math.pow(1 - t, 2) * y1 + 2 * (1 - t) * t * yi + Math.pow(t, 2) * y2
};
};
/**
* Compute the coordinates of the point positioned
* at length t in the cubic bezier curve.
*
* @param {number} t In [0,1] the step percentage to reach
* the point in the curve from the context point.
* @param {number} x1 The X coordinate of the context point.
* @param {number} y1 The Y coordinate of the context point.
* @param {number} x2 The X coordinate of the end point.
* @param {number} y2 The Y coordinate of the end point.
* @param {number} cx The X coordinate of the first control point.
* @param {number} cy The Y coordinate of the first control point.
* @param {number} dx The X coordinate of the second control point.
* @param {number} dy The Y coordinate of the second control point.
* @return {object} {x,y} The point at t.
*/
sigma.utils.getPointOnBezierCurve =
function(t, x1, y1, x2, y2, cx, cy, dx, dy) {
// http://stackoverflow.com/a/15397596
// Blending functions:
var B0_t = Math.pow(1 - t, 3),
B1_t = 3 * t * Math.pow(1 - t, 2),
B2_t = 3 * Math.pow(t, 2) * (1 - t),
B3_t = Math.pow(t, 3);
return {
x: (B0_t * x1) + (B1_t * cx) + (B2_t * dx) + (B3_t * x2),
y: (B0_t * y1) + (B1_t * cy) + (B2_t * dy) + (B3_t * y2)
};
};
/**
* Return the coordinates of the two control points for a self loop (i.e.
* where the start point is also the end point) computed as a cubic bezier
* curve.
*
* @param {number} x The X coordinate of the node.
* @param {number} y The Y coordinate of the node.
* @param {number} size The node size.
* @return {x1,y1,x2,y2} The coordinates of the two control points.
*/
sigma.utils.getSelfLoopControlPoints = function(x , y, size) {
return {
x1: x - size * 7,
y1: y,
x2: x,
y2: y + size * 7
};
};
/**
* Return the euclidian distance between two points of a plane
* with an orthonormal basis.
*
* @param {number} x1 The X coordinate of the first point.
* @param {number} y1 The Y coordinate of the first point.
* @param {number} x2 The X coordinate of the second point.
* @param {number} y2 The Y coordinate of the second point.
* @return {number} The euclidian distance.
*/
sigma.utils.getDistance = function(x0, y0, x1, y1) {
return Math.sqrt(Math.pow(x1 - x0, 2) + Math.pow(y1 - y0, 2));
};
/**
* Return the coordinates of the intersection points of two circles.
*
* @param {number} x0 The X coordinate of center location of the first
* circle.
* @param {number} y0 The Y coordinate of center location of the first
* circle.
* @param {number} r0 The radius of the first circle.
* @param {number} x1 The X coordinate of center location of the second
* circle.
* @param {number} y1 The Y coordinate of center location of the second
* circle.
* @param {number} r1 The radius of the second circle.
* @return {xi,yi} The coordinates of the intersection points.
*/
sigma.utils.getCircleIntersection = function(x0, y0, r0, x1, y1, r1) {
// http://stackoverflow.com/a/12219802
var a, dx, dy, d, h, rx, ry, x2, y2;
// dx and dy are the vertical and horizontal distances between the circle
// centers:
dx = x1 - x0;
dy = y1 - y0;
// Determine the straight-line distance between the centers:
d = Math.sqrt((dy * dy) + (dx * dx));
// Check for solvability:
if (d > (r0 + r1)) {
// No solution. circles do not intersect.
return false;
}
if (d < Math.abs(r0 - r1)) {
// No solution. one circle is contained in the other.
return false;
}
//'point 2' is the point where the line through the circle intersection
// points crosses the line between the circle centers.
// Determine the distance from point 0 to point 2:
a = ((r0 * r0) - (r1 * r1) + (d * d)) / (2.0 * d);
// Determine the coordinates of point 2:
x2 = x0 + (dx * a / d);
y2 = y0 + (dy * a / d);
// Determine the distance from point 2 to either of the intersection
// points:
h = Math.sqrt((r0 * r0) - (a * a));
// Determine the offsets of the intersection points from point 2:
rx = -dy * (h / d);
ry = dx * (h / d);
// Determine the absolute intersection points:
var xi = x2 + rx;
var xi_prime = x2 - rx;
var yi = y2 + ry;
var yi_prime = y2 - ry;
return {xi: xi, xi_prime: xi_prime, yi: yi, yi_prime: yi_prime};
};
/**
* Check if a point is on a line segment.
*
* @param {number} x The X coordinate of the point to check.
* @param {number} y The Y coordinate of the point to check.
* @param {number} x1 The X coordinate of the line start point.
* @param {number} y1 The Y coordinate of the line start point.
* @param {number} x2 The X coordinate of the line end point.
* @param {number} y2 The Y coordinate of the line end point.
* @param {number} epsilon The precision (consider the line thickness).
* @return {boolean} True if point is "close to" the line
* segment, false otherwise.
*/
sigma.utils.isPointOnSegment = function(x, y, x1, y1, x2, y2, epsilon) {
// http://stackoverflow.com/a/328122
var crossProduct = Math.abs((y - y1) * (x2 - x1) - (x - x1) * (y2 - y1)),
d = sigma.utils.getDistance(x1, y1, x2, y2),
nCrossProduct = crossProduct / d; // normalized cross product
return (nCrossProduct < epsilon &&
Math.min(x1, x2) <= x && x <= Math.max(x1, x2) &&
Math.min(y1, y2) <= y && y <= Math.max(y1, y2));
};
/**
* Check if a point is on a quadratic bezier curve segment with a thickness.
*
* @param {number} x The X coordinate of the point to check.
* @param {number} y The Y coordinate of the point to check.
* @param {number} x1 The X coordinate of the curve start point.
* @param {number} y1 The Y coordinate of the curve start point.
* @param {number} x2 The X coordinate of the curve end point.
* @param {number} y2 The Y coordinate of the curve end point.
* @param {number} cpx The X coordinate of the curve control point.
* @param {number} cpy The Y coordinate of the curve control point.
* @param {number} epsilon The precision (consider the line thickness).
* @return {boolean} True if (x,y) is on the curve segment,
* false otherwise.
*/
sigma.utils.isPointOnQuadraticCurve =
function(x, y, x1, y1, x2, y2, cpx, cpy, epsilon) {
// Fails if the point is too far from the extremities of the segment,
// preventing for more costly computation:
var dP1P2 = sigma.utils.getDistance(x1, y1, x2, y2);
if (Math.abs(x - x1) > dP1P2 || Math.abs(y - y1) > dP1P2) {
return false;
}
var dP1 = sigma.utils.getDistance(x, y, x1, y1),
dP2 = sigma.utils.getDistance(x, y, x2, y2),
t = 0.5,
r = (dP1 < dP2) ? -0.01 : 0.01,
rThreshold = 0.001,
i = 100,
pt = sigma.utils.getPointOnQuadraticCurve(t, x1, y1, x2, y2, cpx, cpy),
dt = sigma.utils.getDistance(x, y, pt.x, pt.y),
old_dt;
// This algorithm minimizes the distance from the point to the curve. It
// find the optimal t value where t=0 is the start point and t=1 is the end
// point of the curve, starting from t=0.5.
// It terminates because it runs a maximum of i interations.
while (i-- > 0 &&
t >= 0 && t <= 1 &&
(dt > epsilon) &&
(r > rThreshold || r < -rThreshold)) {
old_dt = dt;
pt = sigma.utils.getPointOnQuadraticCurve(t, x1, y1, x2, y2, cpx, cpy);
dt = sigma.utils.getDistance(x, y, pt.x, pt.y);
if (dt > old_dt) {
// not the right direction:
// halfstep in the opposite direction
r = -r / 2;
t += r;
}
else if (t + r < 0 || t + r > 1) {
// oops, we've gone too far:
// revert with a halfstep
r = r / 2;
dt = old_dt;
}
else {
// progress:
t += r;
}
}
return dt < epsilon;
};
/**
* Check if a point is on a cubic bezier curve segment with a thickness.
*
* @param {number} x The X coordinate of the point to check.
* @param {number} y The Y coordinate of the point to check.
* @param {number} x1 The X coordinate of the curve start point.
* @param {number} y1 The Y coordinate of the curve start point.
* @param {number} x2 The X coordinate of the curve end point.
* @param {number} y2 The Y coordinate of the curve end point.
* @param {number} cpx1 The X coordinate of the 1st curve control point.
* @param {number} cpy1 The Y coordinate of the 1st curve control point.
* @param {number} cpx2 The X coordinate of the 2nd curve control point.
* @param {number} cpy2 The Y coordinate of the 2nd curve control point.
* @param {number} epsilon The precision (consider the line thickness).
* @return {boolean} True if (x,y) is on the curve segment,
* false otherwise.
*/
sigma.utils.isPointOnBezierCurve =
function(x, y, x1, y1, x2, y2, cpx1, cpy1, cpx2, cpy2, epsilon) {
// Fails if the point is too far from the extremities of the segment,
// preventing for more costly computation:
var dP1CP1 = sigma.utils.getDistance(x1, y1, cpx1, cpy1);
if (Math.abs(x - x1) > dP1CP1 || Math.abs(y - y1) > dP1CP1) {
return false;
}
var dP1 = sigma.utils.getDistance(x, y, x1, y1),
dP2 = sigma.utils.getDistance(x, y, x2, y2),
t = 0.5,
r = (dP1 < dP2) ? -0.01 : 0.01,
rThreshold = 0.001,
i = 100,
pt = sigma.utils.getPointOnBezierCurve(
t, x1, y1, x2, y2, cpx1, cpy1, cpx2, cpy2),
dt = sigma.utils.getDistance(x, y, pt.x, pt.y),
old_dt;
// This algorithm minimizes the distance from the point to the curve. It
// find the optimal t value where t=0 is the start point and t=1 is the end
// point of the curve, starting from t=0.5.
// It terminates because it runs a maximum of i interations.
while (i-- > 0 &&
t >= 0 && t <= 1 &&
(dt > epsilon) &&
(r > rThreshold || r < -rThreshold)) {
old_dt = dt;
pt = sigma.utils.getPointOnBezierCurve(
t, x1, y1, x2, y2, cpx1, cpy1, cpx2, cpy2);
dt = sigma.utils.getDistance(x, y, pt.x, pt.y);
if (dt > old_dt) {
// not the right direction:
// halfstep in the opposite direction
r = -r / 2;
t += r;
}
else if (t + r < 0 || t + r > 1) {
// oops, we've gone too far:
// revert with a halfstep
r = r / 2;
dt = old_dt;
}
else {
// progress:
t += r;
}
}
return dt < epsilon;
};
/**
* ************
* EVENTS UTILS:
* ************
*/
/**
* Here are some useful functions to unify extraction of the information we
* need with mouse events and touch events, from different browsers:
*/
/**
* Extract the local X position from a mouse or touch event.
*
* @param {event} e A mouse or touch event.
* @return {number} The local X value of the mouse.
*/
sigma.utils.getX = function(e) {
return (
(e.offsetX !== undefined && e.offsetX) ||
(e.layerX !== undefined && e.layerX) ||
(e.clientX !== undefined && e.clientX)
);
};
/**
* Extract the local Y position from a mouse or touch event.
*
* @param {event} e A mouse or touch event.
* @return {number} The local Y value of the mouse.
*/
sigma.utils.getY = function(e) {
return (
(e.offsetY !== undefined && e.offsetY) ||
(e.layerY !== undefined && e.layerY) ||
(e.clientY !== undefined && e.clientY)
);
};
/**
* The pixel ratio of the screen. Taking zoom into account
*
* @return {number} Pixel ratio of the screen
*/
sigma.utils.getPixelRatio = function() {
var ratio = 1;
if (window.screen.deviceXDPI !== undefined &&
window.screen.logicalXDPI !== undefined &&
window.screen.deviceXDPI > window.screen.logicalXDPI) {
ratio = window.screen.systemXDPI / window.screen.logicalXDPI;
}
else if (window.devicePixelRatio !== undefined) {
ratio = window.devicePixelRatio;
}
return ratio;
};
/**
* Extract the width from a mouse or touch event.
*
* @param {event} e A mouse or touch event.
* @return {number} The width of the event's target.
*/
sigma.utils.getWidth = function(e) {
var w = (!e.target.ownerSVGElement) ?
e.target.width :
e.target.ownerSVGElement.width;
return (
(typeof w === 'number' && w) ||
(w !== undefined && w.baseVal !== undefined && w.baseVal.value)
);
};
/**
* Extract the center from a mouse or touch event.
*
* @param {event} e A mouse or touch event.
* @return {object} The center of the event's target.
*/
sigma.utils.getCenter = function(e) {
var ratio = e.target.namespaceURI.indexOf('svg') !== -1 ? 1 :
sigma.utils.getPixelRatio();
return {
x: sigma.utils.getWidth(e) / (2 * ratio),
y: sigma.utils.getHeight(e) / (2 * ratio)
};
};
/**
* Convert mouse coords to sigma coords
*
* @param {event} e A mouse or touch event.
* @param {number?} x The x coord to convert
* @param {number?} x The y coord to convert
*
* @return {object} The standardized event
*/
sigma.utils.mouseCoords = function(e, x, y) {
x = x || sigma.utils.getX(e);
y = y || sigma.utils.getY(e);
return {
x: x - sigma.utils.getCenter(e).x,
y: y - sigma.utils.getCenter(e).y,
clientX: e.clientX,
clientY: e.clientY,
ctrlKey: e.ctrlKey,
metaKey: e.metaKey,
altKey: e.altKey,
shiftKey: e.shiftKey
};
};
/**
* Extract the height from a mouse or touch event.
*
* @param {event} e A mouse or touch event.
* @return {number} The height of the event's target.
*/
sigma.utils.getHeight = function(e) {
var h = (!e.target.ownerSVGElement) ?
e.target.height :
e.target.ownerSVGElement.height;
return (
(typeof h === 'number' && h) ||
(h !== undefined && h.baseVal !== undefined && h.baseVal.value)
);
};
/**
* Extract the wheel delta from a mouse or touch event.
*
* @param {event} e A mouse or touch event.
* @return {number} The wheel delta of the mouse.
*/
sigma.utils.getDelta = function(e) {
return (
(e.wheelDelta !== undefined && e.wheelDelta) ||
(e.detail !== undefined && -e.detail)
);
};
/**
* Returns the offset of a DOM element.
*
* @param {DOMElement} dom The element to retrieve the position.
* @return {object} The offset of the DOM element (top, left).
*/
sigma.utils.getOffset = function(dom) {
var left = 0,
top = 0;
while (dom) {
top = top + parseInt(dom.offsetTop);
left = left + parseInt(dom.offsetLeft);
dom = dom.offsetParent;
}
return {
top: top,
left: left
};
};
/**
* Simulates a "double click" event.
*
* @param {HTMLElement} target The event target.
* @param {string} type The event type.
* @param {function} callback The callback to execute.
*/
sigma.utils.doubleClick = function(target, type, callback) {
var clicks = 0,
self = this,
handlers;
target._doubleClickHandler = target._doubleClickHandler || {};
target._doubleClickHandler[type] = target._doubleClickHandler[type] || [];
handlers = target._doubleClickHandler[type];
handlers.push(function(e) {
clicks++;
if (clicks === 2) {
clicks = 0;
return callback(e);
} else if (clicks === 1) {
setTimeout(function() {
clicks = 0;
}, sigma.settings.doubleClickTimeout);
}
});
target.addEventListener(type, handlers[handlers.length - 1], false);
};
/**
* Unbind simulated "double click" events.
*
* @param {HTMLElement} target The event target.
* @param {string} type The event type.
*/
sigma.utils.unbindDoubleClick = function(target, type) {
var handler,
handlers = (target._doubleClickHandler || {})[type] || [];
while ((handler = handlers.pop())) {
target.removeEventListener(type, handler);
}
delete (target._doubleClickHandler || {})[type];
};
/**
* Here are just some of the most basic easing functions, used for the
* animated camera "goTo" calls.
*
* If you need some more easings functions, don't hesitate to add them to
* sigma.utils.easings. But I will not add some more here or merge PRs
* containing, because I do not want sigma sources full of overkill and never
* used stuff...
*/
sigma.utils.easings = sigma.utils.easings || {};
sigma.utils.easings.linearNone = function(k) {
return k;
};
sigma.utils.easings.quadraticIn = function(k) {
return k * k;
};
sigma.utils.easings.quadraticOut = function(k) {
return k * (2 - k);
};
sigma.utils.easings.quadraticInOut = function(k) {
if ((k *= 2) < 1)
return 0.5 * k * k;
return - 0.5 * (--k * (k - 2) - 1);
};
sigma.utils.easings.cubicIn = function(k) {
return k * k * k;
};
sigma.utils.easings.cubicOut = function(k) {
return --k * k * k + 1;
};
sigma.utils.easings.cubicInOut = function(k) {
if ((k *= 2) < 1)
return 0.5 * k * k * k;
return 0.5 * ((k -= 2) * k * k + 2);
};
/**
* ************
* WEBGL UTILS:
* ************
*/
/**
* Loads a WebGL shader and returns it.
*
* @param {WebGLContext} gl The WebGLContext to use.
* @param {string} shaderSource The shader source.
* @param {number} shaderType The type of shader.
* @param {function(string): void} error Callback for errors.
* @return {WebGLShader} The created shader.
*/
sigma.utils.loadShader = function(gl, shaderSource, shaderType, error) {
var compiled,
shader = gl.createShader(shaderType);
// Load the shader source
gl.shaderSource(shader, shaderSource);
// Compile the shader
gl.compileShader(shader);
// Check the compile status
compiled = gl.getShaderParameter(shader, gl.COMPILE_STATUS);
// If something went wrong:
if (!compiled) {
if (error) {
error(
'Error compiling shader "' + shader + '":' +
gl.getShaderInfoLog(shader)
);
}
gl.deleteShader(shader);
return null;
}
return shader;
};
/**
* Creates a program, attaches shaders, binds attrib locations, links the
* program and calls useProgram.
*
* @param {Array.<WebGLShader>} shaders The shaders to attach.
* @param {Array.<string>} attribs The attribs names.
* @param {Array.<number>} locations The locations for the attribs.
* @param {function(string): void} error Callback for errors.
* @return {WebGLProgram} The created program.
*/
sigma.utils.loadProgram = function(gl, shaders, attribs, loc, error) {
var i,
linked,
program = gl.createProgram();
for (i = 0; i < shaders.length; ++i)
gl.attachShader(program, shaders[i]);
if (attribs)
for (i = 0; i < attribs.length; ++i)
gl.bindAttribLocation(
program,
locations ? locations[i] : i,
opt_attribs[i]
);
gl.linkProgram(program);
// Check the link status
linked = gl.getProgramParameter(program, gl.LINK_STATUS);
if (!linked) {
if (error)
error('Error in program linking: ' + gl.getProgramInfoLog(program));
gl.deleteProgram(program);
return null;
}
return program;
};
/**
* *********
* MATRICES:
* *********
* The following utils are just here to help generating the transformation
* matrices for the WebGL renderers.
*/
sigma.utils.pkg('sigma.utils.matrices');
/**
* The returns a 3x3 translation matrix.
*
* @param {number} dx The X translation.
* @param {number} dy The Y translation.
* @return {array} Returns the matrix.
*/
sigma.utils.matrices.translation = function(dx, dy) {
return [
1, 0, 0,
0, 1, 0,
dx, dy, 1
];
};
/**
* The returns a 3x3 or 2x2 rotation matrix.
*
* @param {number} angle The rotation angle.
* @param {boolean} m2 If true, the function will return a 2x2 matrix.
* @return {array} Returns the matrix.
*/
sigma.utils.matrices.rotation = function(angle, m2) {
var cos = Math.cos(angle),
sin = Math.sin(angle);
return m2 ? [
cos, -sin,
sin, cos
] : [
cos, -sin, 0,
sin, cos, 0,
0, 0, 1
];
};
/**
* The returns a 3x3 or 2x2 homothetic transformation matrix.
*
* @param {number} ratio The scaling ratio.
* @param {boolean} m2 If true, the function will return a 2x2 matrix.
* @return {array} Returns the matrix.
*/
sigma.utils.matrices.scale = function(ratio, m2) {
return m2 ? [
ratio, 0,
0, ratio
] : [
ratio, 0, 0,
0, ratio, 0,
0, 0, 1
];
};
/**
* The returns a 3x3 or 2x2 homothetic transformation matrix.
*
* @param {array} a The first matrix.
* @param {array} b The second matrix.
* @param {boolean} m2 If true, the function will assume both matrices are
* 2x2.
* @return {array} Returns the matrix.
*/
sigma.utils.matrices.multiply = function(a, b, m2) {
var l = m2 ? 2 : 3,
a00 = a[0 * l + 0],
a01 = a[0 * l + 1],
a02 = a[0 * l + 2],
a10 = a[1 * l + 0],
a11 = a[1 * l + 1],
a12 = a[1 * l + 2],
a20 = a[2 * l + 0],
a21 = a[2 * l + 1],
a22 = a[2 * l + 2],
b00 = b[0 * l + 0],
b01 = b[0 * l + 1],
b02 = b[0 * l + 2],
b10 = b[1 * l + 0],
b11 = b[1 * l + 1],
b12 = b[1 * l + 2],
b20 = b[2 * l + 0],
b21 = b[2 * l + 1],
b22 = b[2 * l + 2];
return m2 ? [
a00 * b00 + a01 * b10,
a00 * b01 + a01 * b11,
a10 * b00 + a11 * b10,
a10 * b01 + a11 * b11
] : [
a00 * b00 + a01 * b10 + a02 * b20,
a00 * b01 + a01 * b11 + a02 * b21,
a00 * b02 + a01 * b12 + a02 * b22,
a10 * b00 + a11 * b10 + a12 * b20,
a10 * b01 + a11 * b11 + a12 * b21,
a10 * b02 + a11 * b12 + a12 * b22,
a20 * b00 + a21 * b10 + a22 * b20,
a20 * b01 + a21 * b11 + a22 * b21,
a20 * b02 + a21 * b12 + a22 * b22
];
};
}).call(this);