boxpointer: Avoid malformed boxpointer arrow

If the arrow's origin is so close to the edge that the arrow will not
be isosceles, we try to compensate as follows:
  - We skip the rounded corner and settle for a right angled arrow as
    as shown below.
    |\_____
    |
    |
  - If the arrow was going to be acute angled, we move the position of
    the box to maintain the arrow's accuracy.

https://bugzilla.gnome.org/show_bug.cgi?id=680077
This commit is contained in:
Debarshi Ray 2012-09-01 16:42:50 +02:00
parent 19f92df8ab
commit 00f15c1075

View File

@ -274,14 +274,51 @@ const BoxPointer = new Lang.Class({
let [x1, y1] = [halfBorder, halfBorder];
let [x2, y2] = [boxWidth - halfBorder, boxHeight - halfBorder];
let skipTopLeft = false;
let skipTopRight = false;
let skipBottomLeft = false;
let skipBottomRight = false;
switch (this._arrowSide) {
case St.Side.TOP:
if (this._arrowOrigin == x1)
skipTopLeft = true;
else if (this._arrowOrigin == x2)
skipTopRight = true;
break;
case St.Side.RIGHT:
if (this._arrowOrigin == y1)
skipTopRight = true;
else if (this._arrowOrigin == y2)
skipBottomRight = true;
break;
case St.Side.BOTTOM:
if (this._arrowOrigin == x1)
skipBottomLeft = true;
else if (this._arrowOrigin == x2)
skipBottomRight = true;
break;
case St.Side.LEFT:
if (this._arrowOrigin == y1)
skipTopLeft = true;
else if (this._arrowOrigin == y2)
skipBottomLeft = true;
break;
}
cr.moveTo(x1 + borderRadius, y1);
if (this._arrowSide == St.Side.TOP) {
if (this._arrowOrigin < (x1 + (borderRadius + halfBase))) {
cr.lineTo(this._arrowOrigin, y1 - rise);
cr.lineTo(Math.max(x1 + borderRadius, this._arrowOrigin) + halfBase, y1);
} else if (this._arrowOrigin > (x2 - (borderRadius + halfBase))) {
cr.lineTo(Math.min(x2 - borderRadius, this._arrowOrigin) - halfBase, y1);
cr.lineTo(this._arrowOrigin, y1 - rise);
if (skipTopLeft) {
cr.moveTo(x1, y2 - borderRadius);
cr.lineTo(x1, y1 - rise);
cr.lineTo(x1 + halfBase, y1);
} else if (skipTopRight) {
cr.lineTo(x2 - halfBase, y1);
cr.lineTo(x2, y1 - rise);
cr.lineTo(x2, y1 + borderRadius);
} else {
cr.lineTo(this._arrowOrigin - halfBase, y1);
cr.lineTo(this._arrowOrigin, y1 - rise);
@ -289,19 +326,21 @@ const BoxPointer = new Lang.Class({
}
}
cr.lineTo(x2 - borderRadius, y1);
if (!skipTopRight) {
// top-right corner
cr.lineTo(x2 - borderRadius, y1);
cr.arc(x2 - borderRadius, y1 + borderRadius, borderRadius,
3*Math.PI/2, Math.PI*2);
}
if (this._arrowSide == St.Side.RIGHT) {
if (this._arrowOrigin < (y1 + (borderRadius + halfBase))) {
cr.lineTo(x2 + rise, this._arrowOrigin);
cr.lineTo(x2, Math.max(y1 + borderRadius, this._arrowOrigin) + halfBase);
} else if (this._arrowOrigin > (y2 - (borderRadius + halfBase))) {
cr.lineTo(x2, Math.min(y2 - borderRadius, this._arrowOrigin) - halfBase);
cr.lineTo(x2 + rise, this._arrowOrigin);
if (skipTopRight) {
cr.lineTo(x2 + rise, y1);
cr.lineTo(x2 + rise, y1 + halfBase);
} else if (skipBottomRight) {
cr.lineTo(x2, y2 - halfBase);
cr.lineTo(x2 + rise, y2);
cr.lineTo(x2 - borderRadius, y2);
} else {
cr.lineTo(x2, this._arrowOrigin - halfBase);
cr.lineTo(x2 + rise, this._arrowOrigin);
@ -309,19 +348,21 @@ const BoxPointer = new Lang.Class({
}
}
cr.lineTo(x2, y2 - borderRadius);
if (!skipBottomRight) {
// bottom-right corner
cr.lineTo(x2, y2 - borderRadius);
cr.arc(x2 - borderRadius, y2 - borderRadius, borderRadius,
0, Math.PI/2);
}
if (this._arrowSide == St.Side.BOTTOM) {
if (this._arrowOrigin < (x1 + (borderRadius + halfBase))) {
cr.lineTo(Math.max(x1 + borderRadius, this._arrowOrigin) + halfBase, y2);
cr.lineTo(this._arrowOrigin, y2 + rise);
} else if (this._arrowOrigin > (x2 - (borderRadius + halfBase))) {
cr.lineTo(this._arrowOrigin, y2 + rise);
cr.lineTo(Math.min(x2 - borderRadius, this._arrowOrigin) - halfBase, y2);
if (skipBottomLeft) {
cr.lineTo(x1 + halfBase, y2);
cr.lineTo(x1, y2 + rise);
cr.lineTo(x1, y2 - borderRadius);
} else if (skipBottomRight) {
cr.lineTo(x2, y2 + rise);
cr.lineTo(x2 - halfBase, y2);
} else {
cr.lineTo(this._arrowOrigin + halfBase, y2);
cr.lineTo(this._arrowOrigin, y2 + rise);
@ -329,19 +370,21 @@ const BoxPointer = new Lang.Class({
}
}
cr.lineTo(x1 + borderRadius, y2);
if (!skipBottomLeft) {
// bottom-left corner
cr.lineTo(x1 + borderRadius, y2);
cr.arc(x1 + borderRadius, y2 - borderRadius, borderRadius,
Math.PI/2, Math.PI);
}
if (this._arrowSide == St.Side.LEFT) {
if (this._arrowOrigin < (y1 + (borderRadius + halfBase))) {
cr.lineTo(x1, Math.max(y1 + borderRadius, this._arrowOrigin) + halfBase);
cr.lineTo(x1 - rise, this._arrowOrigin);
} else if (this._arrowOrigin > (y2 - (borderRadius + halfBase))) {
cr.lineTo(x1 - rise, this._arrowOrigin);
cr.lineTo(x1, Math.min(y2 - borderRadius, this._arrowOrigin) - halfBase);
if (skipTopLeft) {
cr.lineTo(x1, y1 + halfBase);
cr.lineTo(x1 - rise, y1);
cr.lineTo(x1 + borderRadius, y1);
} else if (skipBottomLeft) {
cr.lineTo(x1 - rise, y2)
cr.lineTo(x1 - rise, y2 - halfBase);
} else {
cr.lineTo(x1, this._arrowOrigin + halfBase);
cr.lineTo(x1 - rise, this._arrowOrigin);
@ -349,11 +392,12 @@ const BoxPointer = new Lang.Class({
}
}
cr.lineTo(x1, y1 + borderRadius);
if (!skipTopLeft) {
// top-left corner
cr.lineTo(x1, y1 + borderRadius);
cr.arc(x1 + borderRadius, y1 + borderRadius, borderRadius,
Math.PI, 3*Math.PI/2);
}
Clutter.cairo_set_source_color(cr, backgroundColor);
cr.fillPreserve();
@ -406,9 +450,8 @@ const BoxPointer = new Lang.Class({
let arrowBase = themeNode.get_length('-arrow-base');
let borderRadius = themeNode.get_length('-arrow-border-radius');
let margin = (4 * borderRadius + borderWidth + arrowBase);
let halfMargin = margin / 2;
let themeNode = this.actor.get_theme_node();
let halfMargin = margin / 2;
let gap = themeNode.get_length('-boxpointer-gap');
let padding = themeNode.get_length('-arrow-rise');
@ -429,8 +472,23 @@ const BoxPointer = new Lang.Class({
break;
}
// Now align and position the pointing axis, making sure
// it fits on screen
// Now align and position the pointing axis, making sure it fits on
// screen. If the arrowOrigin is so close to the edge that the arrow
// will not be isosceles, we try to compensate as follows:
// - We skip the rounded corner and settle for a right angled arrow
// as shown below. See _drawBorder for further details.
// |\_____
// |
// |
// - If the arrow was going to be acute angled, we move the position
// of the box to maintain the arrow's accuracy.
let arrowOrigin;
let halfBase = Math.floor(arrowBase/2);
let halfBorder = borderWidth / 2;
let [x1, y1] = [halfBorder, halfBorder];
let [x2, y2] = [natWidth - halfBorder, natHeight - halfBorder];
switch (this._arrowSide) {
case St.Side.TOP:
case St.Side.BOTTOM:
@ -438,7 +496,17 @@ const BoxPointer = new Lang.Class({
resX = Math.max(resX, monitor.x + padding);
resX = Math.min(resX, monitor.x + monitor.width - (padding + natWidth));
this.setArrowOrigin(sourceCenterX - resX);
arrowOrigin = sourceCenterX - resX;
if (arrowOrigin <= (x1 + (borderRadius + halfBase))) {
if (arrowOrigin > x1)
resX += (arrowOrigin - x1);
arrowOrigin = x1;
} else if (arrowOrigin >= (x2 - (borderRadius + halfBase))) {
if (arrowOrigin < x2)
resX -= (x2 - arrowOrigin);
arrowOrigin = x2;
}
break;
case St.Side.LEFT:
@ -448,10 +516,21 @@ const BoxPointer = new Lang.Class({
resY = Math.max(resY, monitor.y + padding);
resY = Math.min(resY, monitor.y + monitor.height - (padding + natHeight));
this.setArrowOrigin(sourceCenterY - resY);
arrowOrigin = sourceCenterY - resY;
if (arrowOrigin <= (y1 + (borderRadius + halfBase))) {
if (arrowOrigin > y1)
resY += (arrowOrigin - y1);
arrowOrigin = y1;
} else if (arrowOrigin >= (y2 - (borderRadius + halfBase))) {
if (arrowOrigin < y2)
resX -= (y2 - arrowOrigin);
arrowOrigin = y2;
}
break;
}
this.setArrowOrigin(arrowOrigin);
let parent = this.actor.get_parent();
let success, x, y;
while (!success) {