skia2/modules/canvaskit/interface.js
Nathaniel Nifong 23b0ed9480 Name name changes suggested in API review
Bug: skia:9843
Change-Id: Ib7e30a129dff17ecde81daa1ff665304908face3
Docs-Preview: https://skia.org/?cl=275048
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/275048
Reviewed-by: Kevin Lubick <kjlubick@google.com>
Commit-Queue: Nathaniel Nifong <nifong@google.com>
2020-03-05 15:13:41 +00:00

1282 lines
43 KiB
JavaScript

// Adds JS functions to augment the CanvasKit interface.
// For example, if there is a wrapper around the C++ call or logic to allow
// chaining, it should go here.
// CanvasKit.onRuntimeInitialized is called after the WASM library has loaded.
// Anything that modifies an exposed class (e.g. SkPath) should be set
// after onRuntimeInitialized, otherwise, it can happen outside of that scope.
CanvasKit.onRuntimeInitialized = function() {
// All calls to 'this' need to go in externs.js so closure doesn't minify them away.
// Add some helpers for matrices. This is ported from SkMatrix.cpp
// to save complexity and overhead of going back and forth between
// C++ and JS layers.
// I would have liked to use something like DOMMatrix, except it
// isn't widely supported (would need polyfills) and it doesn't
// have a mapPoints() function (which could maybe be tacked on here).
// If DOMMatrix catches on, it would be worth re-considering this usage.
CanvasKit.SkMatrix = {};
function sdot() { // to be called with an even number of scalar args
var acc = 0;
for (var i=0; i < arguments.length-1; i+=2) {
acc += arguments[i] * arguments[i+1];
}
return acc;
}
// Private general matrix functions used in both 3x3s and 4x4s.
// Return a square identity matrix of size n.
var identityN = function(n) {
var size = n*n;
var m = new Array(size);
while(size--) {
m[size] = size%(n+1) == 0 ? 1.0 : 0.0;
}
return m;
}
// Stride, a function for compactly representing several ways of copying an array into another.
// Write vector `v` into matrix `m`. `m` is a matrix encoded as an array in row-major
// order. Its width is passed as `width`. `v` is an array with length < (m.length/width).
// An element of `v` is copied into `m` starting at `offset` and moving `colStride` cols right
// each row.
//
// For example, a width of 4, offset of 3, and stride of -1 would put the vector here.
// _ _ 0 _
// _ 1 _ _
// 2 _ _ _
// _ _ _ 3
//
var stride = function(v, m, width, offset, colStride) {
for (var i=0; i<v.length; i++) {
m[i * width + // column
(i * colStride + offset + width) % width // row
] = v[i];
}
return m;
}
CanvasKit.SkMatrix.identity = function() {
return identityN(3);
};
// Return the inverse (if it exists) of this matrix.
// Otherwise, return the identity.
CanvasKit.SkMatrix.invert = function(m) {
// Find the determinant by the sarrus rule. https://en.wikipedia.org/wiki/Rule_of_Sarrus
var det = m[0]*m[4]*m[8] + m[1]*m[5]*m[6] + m[2]*m[3]*m[7]
- m[2]*m[4]*m[6] - m[1]*m[3]*m[8] - m[0]*m[5]*m[7];
if (!det) {
SkDebug('Warning, uninvertible matrix');
return null;
}
// Return the inverse by the formula adj(m)/det.
// adj (adjugate) of a 3x3 is the transpose of it's cofactor matrix.
// a cofactor matrix is a matrix where each term is +-det(N) where matrix N is the 2x2 formed
// by removing the row and column we're currently setting from the source.
// the sign alternates in a checkerboard pattern with a `+` at the top left.
// that's all been combined here into one expression.
return [
(m[4]*m[8] - m[5]*m[7])/det, (m[2]*m[7] - m[1]*m[8])/det, (m[1]*m[5] - m[2]*m[4])/det,
(m[5]*m[6] - m[3]*m[8])/det, (m[0]*m[8] - m[2]*m[6])/det, (m[2]*m[3] - m[0]*m[5])/det,
(m[3]*m[7] - m[4]*m[6])/det, (m[1]*m[6] - m[0]*m[7])/det, (m[0]*m[4] - m[1]*m[3])/det,
];
};
// Maps the given points according to the passed in matrix.
// Results are done in place.
// See SkMatrix.h::mapPoints for the docs on the math.
CanvasKit.SkMatrix.mapPoints = function(matrix, ptArr) {
if (skIsDebug && (ptArr.length % 2)) {
throw 'mapPoints requires an even length arr';
}
for (var i = 0; i < ptArr.length; i+=2) {
var x = ptArr[i], y = ptArr[i+1];
// Gx+Hy+I
var denom = matrix[6]*x + matrix[7]*y + matrix[8];
// Ax+By+C
var xTrans = matrix[0]*x + matrix[1]*y + matrix[2];
// Dx+Ey+F
var yTrans = matrix[3]*x + matrix[4]*y + matrix[5];
ptArr[i] = xTrans/denom;
ptArr[i+1] = yTrans/denom;
}
return ptArr;
};
function isnumber(val) { return val !== NaN; };
// gereralized iterative algorithm for multiplying two matrices.
function multiply(m1, m2, size) {
if (skIsDebug && (!m1.every(isnumber) || !m2.every(isnumber))) {
throw 'Some members of matrices are NaN m1='+m1+', m2='+m2+'';
}
if (skIsDebug && (m1.length !== m2.length)) {
throw 'Undefined for matrices of different sizes. m1.length='+m1.length+', m2.length='+m2.length;
}
if (skIsDebug && (size*size !== m1.length)) {
throw 'Undefined for non-square matrices. array size was '+size;
}
var result = Array(m1.length);
for (var r = 0; r < size; r++) {
for (var c = 0; c < size; c++) {
// accumulate a sum of m1[r,k]*m2[k, c]
var acc = 0;
for (var k = 0; k < size; k++) {
acc += m1[size * r + k] * m2[size * k + c];
}
result[r * size + c] = acc;
}
}
return result;
};
// Accept an integer indicating the size of the matrices being multiplied (3 for 3x3), and any
// number of matrices following it.
function multiplyMany(size, listOfMatrices) {
if (skIsDebug && (listOfMatrices.length < 2)) {
throw 'multiplication expected two or more matrices';
}
var result = multiply(listOfMatrices[0], listOfMatrices[1], size);
var next = 2;
while (next < listOfMatrices.length) {
result = multiply(result, listOfMatrices[next], size);
next++;
}
return result;
};
// Accept any number 3x3 of matrices as arguments, multiply them together.
// Matrix multiplication is associative but not commutatieve. the order of the arguments
// matters, but it does not matter that this implementation multiplies them left to right.
CanvasKit.SkMatrix.multiply = function() {
return multiplyMany(3, arguments);
};
// Return a matrix representing a rotation by n radians.
// px, py optionally say which point the rotation should be around
// with the default being (0, 0);
CanvasKit.SkMatrix.rotated = function(radians, px, py) {
px = px || 0;
py = py || 0;
var sinV = Math.sin(radians);
var cosV = Math.cos(radians);
return [
cosV, -sinV, sdot( sinV, py, 1 - cosV, px),
sinV, cosV, sdot(-sinV, px, 1 - cosV, py),
0, 0, 1,
];
};
CanvasKit.SkMatrix.scaled = function(sx, sy, px, py) {
px = px || 0;
py = py || 0;
var m = stride([sx, sy], identityN(3), 3, 0, 1);
return stride([px-sx*px, py-sy*py], m, 3, 2, 0);
};
CanvasKit.SkMatrix.skewed = function(kx, ky, px, py) {
px = px || 0;
py = py || 0;
var m = stride([kx, ky], identityN(3), 3, 1, -1);
return stride([-kx*px, -ky*py], m, 3, 2, 0);
};
CanvasKit.SkMatrix.translated = function(dx, dy) {
return stride(arguments, identityN(3), 3, 2, 0);
};
// Functions for manipulating vectors.
// Loosely based off of SkV3 in SkM44.h but skia also has SkVec2 and Skv4. This combines them and
// works on vectors of any length.
CanvasKit.SkVector = {};
CanvasKit.SkVector.dot = function(a, b) {
if (skIsDebug && (a.length !== b.length)) {
throw 'Cannot perform dot product on arrays of different length ('+a.length+' vs '+b.length+')';
}
return a.map(function(v, i) { return v*b[i] }).reduce(function(acc, cur) { return acc + cur; });
}
CanvasKit.SkVector.lengthSquared = function(v) {
return CanvasKit.SkVector.dot(v, v);
}
CanvasKit.SkVector.length = function(v) {
return Math.sqrt(CanvasKit.SkVector.lengthSquared(v));
}
CanvasKit.SkVector.mulScalar = function(v, s) {
return v.map(function(i) { return i*s });
}
CanvasKit.SkVector.add = function(a, b) {
return a.map(function(v, i) { return v+b[i] });
}
CanvasKit.SkVector.sub = function(a, b) {
return a.map(function(v, i) { return v-b[i]; });
}
CanvasKit.SkVector.dist = function(a, b) {
return CanvasKit.SkVector.length(CanvasKit.SkVector.sub(a, b));
}
CanvasKit.SkVector.normalize = function(v) {
return CanvasKit.SkVector.mulScalar(v, 1/CanvasKit.SkVector.length(v));
}
CanvasKit.SkVector.cross = function(a, b) {
if (skIsDebug && (a.length !== 3 || a.length !== 3)) {
throw 'Cross product is only defined for 3-dimensional vectors (a.length='+a.length+', b.length='+b.length+')';
}
return [
a[1]*b[2] - a[2]*b[1],
a[2]*b[0] - a[0]*b[2],
a[0]*b[1] - a[1]*b[0],
];
}
// Functions for creating and manipulating 4x4 matrices. Accepted in place of SkM44 in canvas
// methods, for the same reasons as the 3x3 matrices above.
// ported from C++ code in SkM44.cpp
CanvasKit.SkM44 = {};
// Create a 4x4 identity matrix
CanvasKit.SkM44.identity = function() {
return identityN(4);
}
// Anything named vec below is an array of length 3 representing a vector/point in 3D space.
// Create a 4x4 matrix representing a translate by the provided 3-vec
CanvasKit.SkM44.translated = function(vec) {
return stride(vec, identityN(4), 4, 3, 0);
}
// Create a 4x4 matrix representing a scaling by the provided 3-vec
CanvasKit.SkM44.scaled = function(vec) {
return stride(vec, identityN(4), 4, 0, 1);
}
// Create a 4x4 matrix representing a rotation about the provided axis 3-vec.
// axis does not need to be normalized.
CanvasKit.SkM44.rotated = function(axisVec, radians) {
return CanvasKit.SkM44.rotatedUnitSinCos(
CanvasKit.SkVector.normalize(axisVec), Math.sin(radians), Math.cos(radians));
}
// Create a 4x4 matrix representing a rotation about the provided normalized axis 3-vec.
// Rotation is provided redundantly as both sin and cos values.
// This rotate can be used when you already have the cosAngle and sinAngle values
// so you don't have to atan(cos/sin) to call roatated() which expects an angle in radians.
// this does no checking! Behavior for invalid sin or cos values or non-normalized axis vectors
// is incorrect. Prefer rotate().
CanvasKit.SkM44.rotatedUnitSinCos = function(axisVec, sinAngle, cosAngle) {
var x = axisVec[0];
var y = axisVec[1];
var z = axisVec[2];
var c = cosAngle;
var s = sinAngle;
var t = 1 - c;
return [
t*x*x + c, t*x*y - s*z, t*x*z + s*y, 0,
t*x*y + s*z, t*y*y + c, t*y*z - s*x, 0,
t*x*z - s*y, t*y*z + s*x, t*z*z + c, 0,
0, 0, 0, 1
];
}
// Create a 4x4 matrix representing a camera at eyeVec, pointed at centerVec.
CanvasKit.SkM44.lookat = function(eyeVec, centerVec, upVec) {
var f = CanvasKit.SkVector.normalize(CanvasKit.SkVector.sub(centerVec, eyeVec));
var u = CanvasKit.SkVector.normalize(upVec);
var s = CanvasKit.SkVector.normalize(CanvasKit.SkVector.cross(f, u));
var m = CanvasKit.SkM44.identity();
// set each column's top three numbers
stride(s, m, 4, 0, 0);
stride(CanvasKit.SkVector.cross(s, f), m, 4, 1, 0);
stride(CanvasKit.SkVector.mulScalar(f, -1), m, 4, 2, 0);
stride(eyeVec, m, 4, 3, 0);
var m2 = CanvasKit.SkM44.invert(m);
if (m2 === null) {
return CanvasKit.SkM44.identity();
}
return m2;
}
// Create a 4x4 matrix representing a perspective. All arguments are scalars.
// angle is in radians.
CanvasKit.SkM44.perspective = function(near, far, angle) {
if (skIsDebug && (far <= near)) {
throw "far must be greater than near when constructing SkM44 using perspective.";
}
var dInv = 1 / (far - near);
var halfAngle = angle / 2;
var cot = Math.cos(halfAngle) / Math.sin(halfAngle);
return [
cot, 0, 0, 0,
0, cot, 0, 0,
0, 0, (far+near)*dInv, 2*far*near*dInv,
0, 0, -1, 1,
];
}
// Returns the number at the given row and column in matrix m.
CanvasKit.SkM44.rc = function(m, r, c) {
return m[r*4+c];
}
// Accepts any number of 4x4 matrix arguments, multiplies them left to right.
CanvasKit.SkM44.multiply = function() {
return multiplyMany(4, arguments);
}
// Invert the 4x4 matrix if it is invertible and return it. if not, return null.
// taken from SkM44.cpp (altered to use row-major order)
// m is not altered.
CanvasKit.SkM44.invert = function(m) {
if (skIsDebug && !m.every(isnumber)) {
throw 'some members of matrix are NaN m='+m;
}
var a00 = m[0];
var a01 = m[4];
var a02 = m[8];
var a03 = m[12];
var a10 = m[1];
var a11 = m[5];
var a12 = m[9];
var a13 = m[13];
var a20 = m[2];
var a21 = m[6];
var a22 = m[10];
var a23 = m[14];
var a30 = m[3];
var a31 = m[7];
var a32 = m[11];
var a33 = m[15];
var b00 = a00 * a11 - a01 * a10;
var b01 = a00 * a12 - a02 * a10;
var b02 = a00 * a13 - a03 * a10;
var b03 = a01 * a12 - a02 * a11;
var b04 = a01 * a13 - a03 * a11;
var b05 = a02 * a13 - a03 * a12;
var b06 = a20 * a31 - a21 * a30;
var b07 = a20 * a32 - a22 * a30;
var b08 = a20 * a33 - a23 * a30;
var b09 = a21 * a32 - a22 * a31;
var b10 = a21 * a33 - a23 * a31;
var b11 = a22 * a33 - a23 * a32;
// calculate determinate
var det = b00 * b11 - b01 * b10 + b02 * b09 + b03 * b08 - b04 * b07 + b05 * b06;
var invdet = 1.0 / det;
// bail out if the matrix is not invertible
if (det === 0 || invdet === Infinity) {
SkDebug('Warning, uninvertible matrix');
return null;
}
b00 *= invdet;
b01 *= invdet;
b02 *= invdet;
b03 *= invdet;
b04 *= invdet;
b05 *= invdet;
b06 *= invdet;
b07 *= invdet;
b08 *= invdet;
b09 *= invdet;
b10 *= invdet;
b11 *= invdet;
// store result in row major order
var tmp = [
a11 * b11 - a12 * b10 + a13 * b09,
a12 * b08 - a10 * b11 - a13 * b07,
a10 * b10 - a11 * b08 + a13 * b06,
a11 * b07 - a10 * b09 - a12 * b06,
a02 * b10 - a01 * b11 - a03 * b09,
a00 * b11 - a02 * b08 + a03 * b07,
a01 * b08 - a00 * b10 - a03 * b06,
a00 * b09 - a01 * b07 + a02 * b06,
a31 * b05 - a32 * b04 + a33 * b03,
a32 * b02 - a30 * b05 - a33 * b01,
a30 * b04 - a31 * b02 + a33 * b00,
a31 * b01 - a30 * b03 - a32 * b00,
a22 * b04 - a21 * b05 - a23 * b03,
a20 * b05 - a22 * b02 + a23 * b01,
a21 * b02 - a20 * b04 - a23 * b00,
a20 * b03 - a21 * b01 + a22 * b00,
];
if (!tmp.every(function(val) { return val !== NaN && val !== Infinity && val !== -Infinity; })) {
SkDebug('inverted matrix contains infinities or NaN '+tmp);
return null;
}
return tmp;
}
CanvasKit.SkM44.transpose = function(m) {
return [
m[0], m[4], m[8], m[12],
m[1], m[5], m[9], m[13],
m[2], m[6], m[10], m[14],
m[3], m[7], m[11], m[15],
];
}
// An SkColorMatrix is a 4x4 color matrix that transforms the 4 color channels
// with a 1x4 matrix that post-translates those 4 channels.
// For example, the following is the layout with the scale (S) and post-transform
// (PT) items indicated.
// RS, 0, 0, 0 | RPT
// 0, GS, 0, 0 | GPT
// 0, 0, BS, 0 | BPT
// 0, 0, 0, AS | APT
//
// Much of this was hand-transcribed from SkColorMatrix.cpp, because it's easier to
// deal with a Float32Array of length 20 than to try to expose the SkColorMatrix object.
var rScale = 0;
var gScale = 6;
var bScale = 12;
var aScale = 18;
var rPostTrans = 4;
var gPostTrans = 9;
var bPostTrans = 14;
var aPostTrans = 19;
CanvasKit.SkColorMatrix = {};
CanvasKit.SkColorMatrix.identity = function() {
var m = new Float32Array(20);
m[rScale] = 1;
m[gScale] = 1;
m[bScale] = 1;
m[aScale] = 1;
return m;
}
CanvasKit.SkColorMatrix.scaled = function(rs, gs, bs, as) {
var m = new Float32Array(20);
m[rScale] = rs;
m[gScale] = gs;
m[bScale] = bs;
m[aScale] = as;
return m;
}
var rotateIndices = [
[6, 7, 11, 12],
[0, 10, 2, 12],
[0, 1, 5, 6],
];
// axis should be 0, 1, 2 for r, g, b
CanvasKit.SkColorMatrix.rotated = function(axis, sine, cosine) {
var m = CanvasKit.SkColorMatrix.identity();
var indices = rotateIndices[axis];
m[indices[0]] = cosine;
m[indices[1]] = sine;
m[indices[2]] = -sine;
m[indices[3]] = cosine;
return m;
}
// m is a SkColorMatrix (i.e. a Float32Array), and this sets the 4 "special"
// params that will translate the colors after they are multiplied by the 4x4 matrix.
CanvasKit.SkColorMatrix.postTranslate = function(m, dr, dg, db, da) {
m[rPostTrans] += dr;
m[gPostTrans] += dg;
m[bPostTrans] += db;
m[aPostTrans] += da;
return m;
}
// concat returns a new SkColorMatrix that is the result of multiplying outer*inner;
CanvasKit.SkColorMatrix.concat = function(outer, inner) {
var m = new Float32Array(20);
var index = 0;
for (var j = 0; j < 20; j += 5) {
for (var i = 0; i < 4; i++) {
m[index++] = outer[j + 0] * inner[i + 0] +
outer[j + 1] * inner[i + 5] +
outer[j + 2] * inner[i + 10] +
outer[j + 3] * inner[i + 15];
}
m[index++] = outer[j + 0] * inner[4] +
outer[j + 1] * inner[9] +
outer[j + 2] * inner[14] +
outer[j + 3] * inner[19] +
outer[j + 4];
}
return m;
}
CanvasKit.SkPath.prototype.addArc = function(oval, startAngle, sweepAngle) {
// see arc() for the HTMLCanvas version
// note input angles are degrees.
this._addArc(oval, startAngle, sweepAngle);
return this;
};
CanvasKit.SkPath.prototype.addOval = function(oval, isCCW, startIndex) {
if (startIndex === undefined) {
startIndex = 1;
}
this._addOval(oval, !!isCCW, startIndex);
return this;
};
CanvasKit.SkPath.prototype.addPath = function() {
// Takes 1, 2, 7, or 10 required args, where the first arg is always the path.
// The last arg is optional and chooses between add or extend mode.
// The options for the remaining args are:
// - an array of 6 or 9 parameters (perspective is optional)
// - the 9 parameters of a full matrix or
// the 6 non-perspective params of a matrix.
var args = Array.prototype.slice.call(arguments);
var path = args[0];
var extend = false;
if (typeof args[args.length-1] === "boolean") {
extend = args.pop();
}
if (args.length === 1) {
// Add path, unchanged. Use identity matrix
this._addPath(path, 1, 0, 0,
0, 1, 0,
0, 0, 1,
extend);
} else if (args.length === 2) {
// User provided the 9 params of a full matrix as an array.
var a = args[1];
this._addPath(path, a[0], a[1], a[2],
a[3], a[4], a[5],
a[6] || 0, a[7] || 0, a[8] || 1,
extend);
} else if (args.length === 7 || args.length === 10) {
// User provided the 9 params of a (full) matrix directly.
// (or just the 6 non perspective ones)
// These are in the same order as what Skia expects.
var a = args;
this._addPath(path, a[1], a[2], a[3],
a[4], a[5], a[6],
a[7] || 0, a[8] || 0, a[9] || 1,
extend);
} else {
SkDebug('addPath expected to take 1, 2, 7, or 10 required args. Got ' + args.length);
return null;
}
return this;
};
// points is either an array of [x, y] where x and y are numbers or
// a typed array from Malloc where the even indices will be treated
// as x coordinates and the odd indices will be treated as y coordinates.
CanvasKit.SkPath.prototype.addPoly = function(points, close) {
var ptr;
var n;
// This was created with CanvasKit.Malloc, so assume the user has
// already been filled with data.
if (points['_ck']) {
ptr = points.byteOffset;
n = points.length/2;
} else {
ptr = copy2dArray(points, CanvasKit.HEAPF32);
n = points.length;
}
this._addPoly(ptr, n, close);
CanvasKit._free(ptr);
return this;
};
CanvasKit.SkPath.prototype.addRect = function() {
// Takes 1, 2, 4 or 5 args
// - SkRect
// - SkRect, isCCW
// - left, top, right, bottom
// - left, top, right, bottom, isCCW
if (arguments.length === 1 || arguments.length === 2) {
var r = arguments[0];
var ccw = arguments[1] || false;
this._addRect(r.fLeft, r.fTop, r.fRight, r.fBottom, ccw);
} else if (arguments.length === 4 || arguments.length === 5) {
var a = arguments;
this._addRect(a[0], a[1], a[2], a[3], a[4] || false);
} else {
SkDebug('addRect expected to take 1, 2, 4, or 5 args. Got ' + arguments.length);
return null;
}
return this;
};
CanvasKit.SkPath.prototype.addRoundRect = function() {
// Takes 3, 4, 6 or 7 args
// - SkRect, radii, ccw
// - SkRect, rx, ry, ccw
// - left, top, right, bottom, radii, ccw
// - left, top, right, bottom, rx, ry, ccw
var args = arguments;
if (args.length === 3 || args.length === 6) {
var radii = args[args.length-2];
} else if (args.length === 6 || args.length === 7){
// duplicate the given (rx, ry) pairs for each corner.
var rx = args[args.length-3];
var ry = args[args.length-2];
var radii = [rx, ry, rx, ry, rx, ry, rx, ry];
} else {
SkDebug('addRoundRect expected to take 3, 4, 6, or 7 args. Got ' + args.length);
return null;
}
if (radii.length !== 8) {
SkDebug('addRoundRect needs 8 radii provided. Got ' + radii.length);
return null;
}
var rptr = copy1dArray(radii, CanvasKit.HEAPF32);
if (args.length === 3 || args.length === 4) {
var r = args[0];
var ccw = args[args.length - 1];
this._addRoundRect(r.fLeft, r.fTop, r.fRight, r.fBottom, rptr, ccw);
} else if (args.length === 6 || args.length === 7) {
var a = args;
this._addRoundRect(a[0], a[1], a[2], a[3], rptr, ccw);
}
CanvasKit._free(rptr);
return this;
};
CanvasKit.SkPath.prototype.arc = function(x, y, radius, startAngle, endAngle, ccw) {
// emulates the HTMLCanvas behavior. See addArc() for the SkPath version.
// Note input angles are radians.
var bounds = CanvasKit.LTRBRect(x-radius, y-radius, x+radius, y+radius);
var sweep = radiansToDegrees(endAngle - startAngle) - (360 * !!ccw);
var temp = new CanvasKit.SkPath();
temp.addArc(bounds, radiansToDegrees(startAngle), sweep);
this.addPath(temp, true);
temp.delete();
return this;
};
CanvasKit.SkPath.prototype.arcTo = function() {
// takes 4, 5 or 7 args
// - 5 x1, y1, x2, y2, radius
// - 4 oval (as Rect), startAngle, sweepAngle, forceMoveTo
// - 7 rx, ry, xAxisRotate, useSmallArc, isCCW, x, y
var args = arguments;
if (args.length === 5) {
this._arcTo(args[0], args[1], args[2], args[3], args[4]);
} else if (args.length === 4) {
this._arcTo(args[0], args[1], args[2], args[3]);
} else if (args.length === 7) {
this._arcTo(args[0], args[1], args[2], !!args[3], !!args[4], args[5], args[6]);
} else {
throw 'Invalid args for arcTo. Expected 4, 5, or 7, got '+ args.length;
}
return this;
};
CanvasKit.SkPath.prototype.close = function() {
this._close();
return this;
};
CanvasKit.SkPath.prototype.conicTo = function(x1, y1, x2, y2, w) {
this._conicTo(x1, y1, x2, y2, w);
return this;
};
CanvasKit.SkPath.prototype.cubicTo = function(cp1x, cp1y, cp2x, cp2y, x, y) {
this._cubicTo(cp1x, cp1y, cp2x, cp2y, x, y);
return this;
};
CanvasKit.SkPath.prototype.dash = function(on, off, phase) {
if (this._dash(on, off, phase)) {
return this;
}
return null;
};
CanvasKit.SkPath.prototype.lineTo = function(x, y) {
this._lineTo(x, y);
return this;
};
CanvasKit.SkPath.prototype.moveTo = function(x, y) {
this._moveTo(x, y);
return this;
};
CanvasKit.SkPath.prototype.offset = function(dx, dy) {
this._transform(1, 0, dx,
0, 1, dy,
0, 0, 1);
return this;
};
CanvasKit.SkPath.prototype.quadTo = function(cpx, cpy, x, y) {
this._quadTo(cpx, cpy, x, y);
return this;
};
CanvasKit.SkPath.prototype.rArcTo = function(rx, ry, xAxisRotate, useSmallArc, isCCW, dx, dy) {
this._rArcTo(rx, ry, xAxisRotate, useSmallArc, isCCW, dx, dy);
return this;
};
CanvasKit.SkPath.prototype.rConicTo = function(dx1, dy1, dx2, dy2, w) {
this._rConicTo(dx1, dy1, dx2, dy2, w);
return this;
};
// These params are all relative
CanvasKit.SkPath.prototype.rCubicTo = function(cp1x, cp1y, cp2x, cp2y, x, y) {
this._rCubicTo(cp1x, cp1y, cp2x, cp2y, x, y);
return this;
};
CanvasKit.SkPath.prototype.rLineTo = function(dx, dy) {
this._rLineTo(dx, dy);
return this;
};
CanvasKit.SkPath.prototype.rMoveTo = function(dx, dy) {
this._rMoveTo(dx, dy);
return this;
};
// These params are all relative
CanvasKit.SkPath.prototype.rQuadTo = function(cpx, cpy, x, y) {
this._rQuadTo(cpx, cpy, x, y);
return this;
};
CanvasKit.SkPath.prototype.stroke = function(opts) {
// Fill out any missing values with the default values.
/**
* See externs.js for this definition
* @type {StrokeOpts}
*/
opts = opts || {};
opts.width = opts.width || 1;
opts.miter_limit = opts.miter_limit || 4;
opts.cap = opts.cap || CanvasKit.StrokeCap.Butt;
opts.join = opts.join || CanvasKit.StrokeJoin.Miter;
opts.precision = opts.precision || 1;
if (this._stroke(opts)) {
return this;
}
return null;
};
CanvasKit.SkPath.prototype.transform = function() {
// Takes 1 or 9 args
if (arguments.length === 1) {
// argument 1 should be a 6 or 9 element array.
var a = arguments[0];
this._transform(a[0], a[1], a[2],
a[3], a[4], a[5],
a[6] || 0, a[7] || 0, a[8] || 1);
} else if (arguments.length === 6 || arguments.length === 9) {
// these arguments are the 6 or 9 members of the matrix
var a = arguments;
this._transform(a[0], a[1], a[2],
a[3], a[4], a[5],
a[6] || 0, a[7] || 0, a[8] || 1);
} else {
throw 'transform expected to take 1 or 9 arguments. Got ' + arguments.length;
}
return this;
};
// isComplement is optional, defaults to false
CanvasKit.SkPath.prototype.trim = function(startT, stopT, isComplement) {
if (this._trim(startT, stopT, !!isComplement)) {
return this;
}
return null;
};
CanvasKit.SkImage.prototype.encodeToData = function() {
if (!arguments.length) {
return this._encodeToData();
}
if (arguments.length === 2) {
var a = arguments;
return this._encodeToDataWithFormat(a[0], a[1]);
}
throw 'encodeToData expected to take 0 or 2 arguments. Got ' + arguments.length;
}
CanvasKit.SkImage.prototype.makeShader = function(xTileMode, yTileMode, localMatrix) {
if (localMatrix) {
// Add perspective args if not provided.
if (localMatrix.length === 6) {
localMatrix.push(0, 0, 1);
}
return this._makeShader(xTileMode, yTileMode, localMatrix);
} else {
return this._makeShader(xTileMode, yTileMode);
}
}
CanvasKit.SkImage.prototype.readPixels = function(imageInfo, srcX, srcY) {
var rowBytes;
// Important to use ["string"] notation here, otherwise the closure compiler will
// minify away the colorType.
switch (imageInfo["colorType"]) {
case CanvasKit.ColorType.RGBA_8888:
rowBytes = imageInfo.width * 4; // 1 byte per channel == 4 bytes per pixel in 8888
break;
case CanvasKit.ColorType.RGBA_F32:
rowBytes = imageInfo.width * 16; // 4 bytes per channel == 16 bytes per pixel in F32
break;
default:
SkDebug("Colortype not yet supported");
return;
}
var pBytes = rowBytes * imageInfo.height;
var pPtr = CanvasKit._malloc(pBytes);
if (!this._readPixels(imageInfo, pPtr, rowBytes, srcX, srcY)) {
SkDebug("Could not read pixels with the given inputs");
return null;
}
// Put those pixels into a typed array of the right format and then
// make a copy with slice() that we can return.
var retVal = null;
switch (imageInfo["colorType"]) {
case CanvasKit.ColorType.RGBA_8888:
retVal = new Uint8Array(CanvasKit.HEAPU8.buffer, pPtr, pBytes).slice();
break;
case CanvasKit.ColorType.RGBA_F32:
retVal = new Float32Array(CanvasKit.HEAPU8.buffer, pPtr, pBytes).slice();
break;
}
// Free the allocated pixels in the WASM memory
CanvasKit._free(pPtr);
return retVal;
}
// atlas is an SkImage, e.g. from CanvasKit.MakeImageFromEncoded
// srcRects and dstXforms should be CanvasKit.SkRectBuilder and CanvasKit.RSXFormBuilder
// or just arrays of floats in groups of 4.
// colors, if provided, should be a CanvasKit.SkColorBuilder or array of SkColor
// (from CanvasKit.Color)
CanvasKit.SkCanvas.prototype.drawAtlas = function(atlas, srcRects, dstXforms, paint,
/*optional*/ blendMode, colors) {
if (!atlas || !paint || !srcRects || !dstXforms) {
SkDebug('Doing nothing since missing a required input');
return;
}
if (srcRects.length !== dstXforms.length || (colors && colors.length !== dstXforms.length)) {
SkDebug('Doing nothing since input arrays length mismatches');
}
if (!blendMode) {
blendMode = CanvasKit.BlendMode.SrcOver;
}
var srcRectPtr;
if (srcRects.build) {
srcRectPtr = srcRects.build();
} else {
srcRectPtr = copy1dArray(srcRects, CanvasKit.HEAPF32);
}
var dstXformPtr;
if (dstXforms.build) {
dstXformPtr = dstXforms.build();
} else {
dstXformPtr = copy1dArray(dstXforms, CanvasKit.HEAPF32);
}
var colorPtr = 0; // enscriptem doesn't like undefined for nullptr
if (colors) {
if (colors.build) {
colorPtr = colors.build();
} else {
colorPtr = copy1dArray(colors, CanvasKit.HEAPU32);
}
}
this._drawAtlas(atlas, dstXformPtr, srcRectPtr, colorPtr, dstXforms.length,
blendMode, paint);
if (srcRectPtr && !srcRects.build) {
CanvasKit._free(srcRectPtr);
}
if (dstXformPtr && !dstXforms.build) {
CanvasKit._free(dstXformPtr);
}
if (colorPtr && !colors.build) {
CanvasKit._free(colorPtr);
}
}
// points is either an array of [x, y] where x and y are numbers or
// a typed array from Malloc where the even indices will be treated
// as x coordinates and the odd indices will be treated as y coordinates.
CanvasKit.SkCanvas.prototype.drawPoints = function(mode, points, paint) {
var ptr;
var n;
// This was created with CanvasKit.Malloc, so assume the user has
// already been filled with data.
if (points['_ck']) {
ptr = points.byteOffset;
n = points.length/2;
} else {
ptr = copy2dArray(points, CanvasKit.HEAPF32);
n = points.length;
}
this._drawPoints(mode, ptr, n, paint);
CanvasKit._free(ptr);
}
// returns Uint8Array
CanvasKit.SkCanvas.prototype.readPixels = function(x, y, w, h, alphaType,
colorType, dstRowBytes) {
// supply defaults (which are compatible with HTMLCanvas's getImageData)
alphaType = alphaType || CanvasKit.AlphaType.Unpremul;
colorType = colorType || CanvasKit.ColorType.RGBA_8888;
dstRowBytes = dstRowBytes || (4 * w);
var len = h * dstRowBytes
var pptr = CanvasKit._malloc(len);
var ok = this._readPixels({
'width': w,
'height': h,
'colorType': colorType,
'alphaType': alphaType,
}, pptr, dstRowBytes, x, y);
if (!ok) {
CanvasKit._free(pptr);
return null;
}
// The first typed array is just a view into memory. Because we will
// be free-ing that, we call slice to make a persistent copy.
var pixels = new Uint8Array(CanvasKit.HEAPU8.buffer, pptr, len).slice();
CanvasKit._free(pptr);
return pixels;
}
// pixels is a TypedArray. No matter the input size, it will be treated as
// a Uint8Array (essentially, a byte array).
CanvasKit.SkCanvas.prototype.writePixels = function(pixels, srcWidth, srcHeight,
destX, destY, alphaType, colorType) {
if (pixels.byteLength % (srcWidth * srcHeight)) {
throw 'pixels length must be a multiple of the srcWidth * srcHeight';
}
var bytesPerPixel = pixels.byteLength / (srcWidth * srcHeight);
// supply defaults (which are compatible with HTMLCanvas's putImageData)
alphaType = alphaType || CanvasKit.AlphaType.Unpremul;
colorType = colorType || CanvasKit.ColorType.RGBA_8888;
var srcRowBytes = bytesPerPixel * srcWidth;
var pptr = CanvasKit._malloc(pixels.byteLength);
CanvasKit.HEAPU8.set(pixels, pptr);
var ok = this._writePixels({
'width': srcWidth,
'height': srcHeight,
'colorType': colorType,
'alphaType': alphaType,
}, pptr, srcRowBytes, destX, destY);
CanvasKit._free(pptr);
return ok;
}
// colorMatrix is an SkColorMatrix (e.g. Float32Array of length 20)
CanvasKit.SkColorFilter.MakeMatrix = function(colorMatrix) {
if (!colorMatrix || colorMatrix.length !== 20) {
SkDebug('ignoring invalid color matrix');
return;
}
var fptr = copy1dArray(colorMatrix, CanvasKit.HEAPF32);
// We know skia memcopies the floats, so we can free our memory after the call returns.
var m = CanvasKit.SkColorFilter._makeMatrix(fptr);
CanvasKit._free(fptr);
return m;
}
CanvasKit.SkShader.Blend = function(mode, dst, src, localMatrix) {
if (!localMatrix) {
return this._Blend(mode, dst, src);
}
return this._Blend(mode, dst, src, localMatrix);
}
CanvasKit.SkShader.Lerp = function(t, dst, src, localMatrix) {
if (!localMatrix) {
return this._Lerp(t, dst, src);
}
return this._Lerp(t, dst, src, localMatrix);
}
CanvasKit.SkSurface.prototype.captureFrameAsSkPicture = function(drawFrame) {
// Set up SkPictureRecorder
var spr = new CanvasKit.SkPictureRecorder();
var canvas = spr.beginRecording(
CanvasKit.LTRBRect(0, 0, this.width(), this.height()));
drawFrame(canvas);
var pic = spr.finishRecordingAsPicture();
spr.delete();
// TODO: do we need to clean up the memory for canvas?
// If we delete it here, saveAsFile doesn't work correctly.
return pic;
}
CanvasKit.SkSurface.prototype.requestAnimationFrame = function(callback, dirtyRect) {
if (!this._cached_canvas) {
this._cached_canvas = this.getCanvas();
}
window.requestAnimationFrame(function() {
if (this._context !== undefined) {
CanvasKit.setCurrentContext(this._context);
}
callback(this._cached_canvas);
// We do not dispose() of the SkSurface here, as the client will typically
// call requestAnimationFrame again from within the supplied callback.
// For drawing a single frame, prefer drawOnce().
this.flush();
}.bind(this));
}
// drawOnce will dispose of the surface after drawing the frame using the provided
// callback.
CanvasKit.SkSurface.prototype.drawOnce = function(callback, dirtyRect) {
if (!this._cached_canvas) {
this._cached_canvas = this.getCanvas();
}
window.requestAnimationFrame(function() {
if (this._context !== undefined) {
CanvasKit.setCurrentContext(this._context);
}
callback(this._cached_canvas);
this.flush();
this.dispose();
}.bind(this));
}
CanvasKit.SkPathEffect.MakeDash = function(intervals, phase) {
if (!phase) {
phase = 0;
}
if (!intervals.length || intervals.length % 2 === 1) {
throw 'Intervals array must have even length';
}
var ptr = copy1dArray(intervals, CanvasKit.HEAPF32);
var dpe = CanvasKit._MakeSkDashPathEffect(ptr, intervals.length, phase);
CanvasKit._free(ptr);
return dpe;
}
CanvasKit.SkShader.MakeLinearGradient = function(start, end, colors, pos, mode, localMatrix, flags) {
var colorPtr = copy1dArray(colors, CanvasKit.HEAPU32);
var posPtr = copy1dArray(pos, CanvasKit.HEAPF32);
flags = flags || 0;
if (localMatrix) {
// Add perspective args if not provided.
if (localMatrix.length === 6) {
localMatrix.push(0, 0, 1);
}
var lgs = CanvasKit._MakeLinearGradientShader(start, end, colorPtr, posPtr,
colors.length, mode, flags, localMatrix);
} else {
var lgs = CanvasKit._MakeLinearGradientShader(start, end, colorPtr, posPtr,
colors.length, mode, flags);
}
CanvasKit._free(colorPtr);
CanvasKit._free(posPtr);
return lgs;
}
CanvasKit.SkShader.MakeRadialGradient = function(center, radius, colors, pos, mode, localMatrix, flags) {
var colorPtr = copy1dArray(colors, CanvasKit.HEAPU32);
var posPtr = copy1dArray(pos, CanvasKit.HEAPF32);
flags = flags || 0;
if (localMatrix) {
// Add perspective args if not provided.
if (localMatrix.length === 6) {
localMatrix.push(0, 0, 1);
}
var rgs = CanvasKit._MakeRadialGradientShader(center, radius, colorPtr, posPtr,
colors.length, mode, flags, localMatrix);
} else {
var rgs = CanvasKit._MakeRadialGradientShader(center, radius, colorPtr, posPtr,
colors.length, mode, flags);
}
CanvasKit._free(colorPtr);
CanvasKit._free(posPtr);
return rgs;
}
CanvasKit.SkShader.MakeTwoPointConicalGradient = function(start, startRadius, end, endRadius,
colors, pos, mode, localMatrix, flags) {
var colorPtr = copy1dArray(colors, CanvasKit.HEAPU32);
var posPtr = copy1dArray(pos, CanvasKit.HEAPF32);
flags = flags || 0;
if (localMatrix) {
// Add perspective args if not provided.
if (localMatrix.length === 6) {
localMatrix.push(0, 0, 1);
}
var rgs = CanvasKit._MakeTwoPointConicalGradientShader(
start, startRadius, end, endRadius,
colorPtr, posPtr, colors.length, mode, flags, localMatrix);
} else {
var rgs = CanvasKit._MakeTwoPointConicalGradientShader(
start, startRadius, end, endRadius,
colorPtr, posPtr, colors.length, mode, flags);
}
CanvasKit._free(colorPtr);
CanvasKit._free(posPtr);
return rgs;
}
// temporary support for deprecated names.
CanvasKit.MakeSkDashPathEffect = CanvasKit.SkPathEffect.prototype.MakeDash;
CanvasKit.MakeLinearGradientShader = CanvasKit.SkShader.prototype.MakeLinearGradient;
CanvasKit.MakeRadialGradientShader = CanvasKit.SkShader.prototype.MakeRadialGradient;
CanvasKit.MakeTwoPointConicalGradientShader = CanvasKit.SkShader.prototype.MakeTwoPointConicalGradient;
// Run through the JS files that are added at compile time.
if (CanvasKit._extraInitializations) {
CanvasKit._extraInitializations.forEach(function(init) {
init();
});
}
}; // end CanvasKit.onRuntimeInitialized, that is, anything changing prototypes or dynamic.
CanvasKit.LTRBRect = function(l, t, r, b) {
return {
fLeft: l,
fTop: t,
fRight: r,
fBottom: b,
};
}
CanvasKit.XYWHRect = function(x, y, w, h) {
return {
fLeft: x,
fTop: y,
fRight: x+w,
fBottom: y+h,
};
}
// RRectXY returns an RRect with the given rect and a radiusX and radiusY for
// all 4 corners.
CanvasKit.RRectXY = function(rect, rx, ry) {
return {
rect: rect,
rx1: rx,
ry1: ry,
rx2: rx,
ry2: ry,
rx3: rx,
ry3: ry,
rx4: rx,
ry4: ry,
};
}
CanvasKit.MakePathFromCmds = function(cmds) {
var ptrLen = loadCmdsTypedArray(cmds);
var path = CanvasKit._MakePathFromCmds(ptrLen[0], ptrLen[1]);
CanvasKit._free(ptrLen[0]);
return path;
}
// data is a TypedArray or ArrayBuffer e.g. from fetch().then(resp.arrayBuffer())
CanvasKit.MakeAnimatedImageFromEncoded = function(data) {
data = new Uint8Array(data);
var iptr = CanvasKit._malloc(data.byteLength);
CanvasKit.HEAPU8.set(data, iptr);
var img = CanvasKit._decodeAnimatedImage(iptr, data.byteLength);
if (!img) {
SkDebug('Could not decode animated image');
return null;
}
return img;
}
// data is a TypedArray or ArrayBuffer e.g. from fetch().then(resp.arrayBuffer())
CanvasKit.MakeImageFromEncoded = function(data) {
data = new Uint8Array(data);
var iptr = CanvasKit._malloc(data.byteLength);
CanvasKit.HEAPU8.set(data, iptr);
var img = CanvasKit._decodeImage(iptr, data.byteLength);
if (!img) {
SkDebug('Could not decode image');
return null;
}
return img;
}
// pixels must be a Uint8Array with bytes representing the pixel values
// (e.g. each set of 4 bytes could represent RGBA values for a single pixel).
CanvasKit.MakeImage = function(pixels, width, height, alphaType, colorType) {
var bytesPerPixel = pixels.length / (width * height);
var info = {
'width': width,
'height': height,
'alphaType': alphaType,
'colorType': colorType,
};
var pptr = copy1dArray(pixels, CanvasKit.HEAPU8);
// No need to _free pptr, Image takes it with SkData::MakeFromMalloc
return CanvasKit._MakeImage(info, pptr, pixels.length, width * bytesPerPixel);
}
CanvasKit.MakeSkVertices = function(mode, positions, textureCoordinates, colors,
indices, isVolatile) {
// Default isVolitile to true if not set
isVolatile = isVolatile === undefined ? true : isVolatile;
var idxCount = (indices && indices.length) || 0;
var flags = 0;
// These flags are from SkVertices.h and should be kept in sync with those.
if (textureCoordinates && textureCoordinates.length) {
flags |= (1 << 0);
}
if (colors && colors.length) {
flags |= (1 << 1);
}
if (!isVolatile) {
flags |= (1 << 2);
}
var builder = new CanvasKit._SkVerticesBuilder(mode, positions.length, idxCount, flags);
copy2dArray(positions, CanvasKit.HEAPF32, builder.positions());
if (builder.texCoords()) {
copy2dArray(textureCoordinates, CanvasKit.HEAPF32, builder.texCoords());
}
if (builder.colors()) {
copy1dArray(colors, CanvasKit.HEAPU32, builder.colors());
}
if (builder.indices()) {
copy1dArray(indices, CanvasKit.HEAPU16, builder.indices());
}
var idxCount = (indices && indices.length) || 0;
// Create the vertices, which owns the memory that the builder had allocated.
return builder.detach();
};