function dropShadow(paintFn) {
var success;
var saveBlendMode = vg.getI(vg.VGParamType.VG_BLEND_MODE);
vg.getMatrix(shadowTransform);
success = vg.egl.makeCurrent(shadowSurface, shadowContext);
vg.loadMatrix(shadowTransform);
vg.clear(0, 0, width, height);
vg.translate(shadowOffsetX, shadowOffsetY);
paintFn();
vg.translate(-shadowOffsetX, -shadowOffsetY);
vg.setI(vg.VGParamType.VG_BLEND_MODE, vg.VGBlendMode.VG_BLEND_SRC_IN);
vg.setParameterI(shadowPaint, vg.VGPaintParamType.VG_PAINT_TYPE,
vg.VGPaintType.VG_PAINT_TYPE_COLOR);
vg.setParameterFV(shadowPaint, vg.VGPaintParamType.VG_PAINT_COLOR,
shadowColor);
vg.setPaint(shadowPaint, vg.VGPaintMode.VG_FILL_PATH);
vg.getMatrix(shadowTransform);
vg.loadIdentity();
var vgPath = vg.createPath(vg.VG_PATH_FORMAT_STANDARD,
vg.VGPathDatatype.VG_PATH_DATATYPE_F,
1.0 /* scale */ , 0.0 /* bias */,
5 /* segCapacityHint */,
5 /* coordCapacityHint */,
vg.VGPathCapabilities.VG_PATH_CAPABILITY_APPEND_TO);
vg.vgu.rect(vgPath, 0, 0, width, height);
vg.drawPath(vgPath, vg.VGPaintMode.VG_FILL_PATH);
vg.destroyPath(vgPath);
vg.loadMatrix(shadowTransform);
vg.setI(vg.VGParamType.VG_BLEND_MODE, vg.VGBlendMode.VG_BLEND_SRC_OVER);
if (shadowBlur !== 0) {
var sigma = shadowBlur / 2;
vg.gaussianBlur(shadowDstImage, shadowSrcImage,
sigma, sigma,
vg.VGTilingMode.VG_TILE_PAD);
}
success = vg.egl.makeCurrent(vg.screen.surface, vg.screen.context);
vg.setI(vg.VGParamType.VG_BLEND_MODE, vg.VGBlendMode.VG_BLEND_SRC_OVER);
vg.getMatrix(shadowTransform);
vg.loadIdentity();
vg.drawImage(shadowBlur !== 0 ? shadowDstImage : shadowSrcImage);
vg.loadMatrix(shadowTransform);
vg.setI(vg.VGParamType.VG_BLEND_MODE, saveBlendMode);
}
function (textPath, idx, character) {
var glyph = typeface.characterMap[character];
// 1. Let dx be the x-coordinate of the horizontal center of the
// bounding box of the shape described by glyph, in CSS pixels.
var bbox = typeface.glyphBBoxes[glyph];
var hCenter = (bbox.minX + (bbox.maxX - bbox.minX) / 2) * size / 65536.0;
var dx = renderInfo.glyphPositions[idx].x + hCenter;
// 2. If dx is negative or greater than width, skip the remainder or
// these substeps for this glyph.
if (dx < 0 || dx > width) return false;
// 3. Recast dx to coordinate spaces units in path. (This just changes
// the dimensionality of dx, not its numeric value.)
// WAT !?
// 4. Find the point p on path (or implied closing lines in path) that
// corresponds to the position dx on the coordinate line L.
vg.pointAlongPath(path.vgPath, 0, pathNumSegments, dx, pointInfo);
// 5. Let θ be the clockwise angle from the positive x-axis to the side
// of the line that is tangential to path at the point p that is
// going in the same direction as the line at point p.
var theta = Math.atan2(pointInfo.ty, pointInfo.tx);
// 6. Rotate the shape described by glyph clockwise by θ about the
// point that is at the dx coordinate horizontally and the zero
// coordinate vertically.
// 7. Let (x, y) be the coordinate of the point p.
// 8. Move the shape described by glyph to the right by x and down by
// y.
// This operations must be run in reverse order.
vg.translate(pointInfo.x, pointInfo.y);
vg.rotate(theta * 180 / Math.PI);
vg.translate(-hCenter, renderInfo.anchor.y);
vg.scale(size * renderInfo.scaleX, -size);
// 9. Let glyph subpaths be a list of subpaths describing the shape
// given in glyph, with each CSS pixel in the coordinate space of
// glyph mapped to one coordinate space unit in glyph subpaths.
// Subpaths in glyph subpaths must wind clockwise, regardless of
// how the user agent's font subsystem renders fonts and
// regardless of how the fonts themselves are defined.
// Nothing to do here (maybe?)
// 10. If the method is addPathByStrokingText(), replace glyph
// subpaths by the result of tracing glyph subpaths, using the
// CanvasDrawingStyles object argument for the line styles.
// Nothing to do here (no support for addPathByStrokingText for now)
// 11. Transform all the coordinates and lines in glyph subpaths by
// the transformation matrix transform, if it is not null.
// See 9. below
// 12. Let (xfinal, yfinal) be the last point in the last subpath of
// glyph subpaths. (This coordinate is only used if this is the
// last glyph processed.)
// TODO Complement loading so that this point is stored
// 13. Add all the subpaths in glyph subpaths to target.
vg.transformPath(textPath, typeface.glyphs[glyph]);
});
result.translate = function (x, y) {
vg.translate(x, y);
};