Merge pull request #339 from juliandescottes/add-straight-lines

Issue #146 : Draw straight lines
This commit is contained in:
Julian Descottes 2015-11-20 00:16:18 +01:00
commit cfe3545eec

View File

@ -10,6 +10,9 @@
this.toolId = 'tool-stroke';
this.helpText = 'Stroke tool';
this.shortcut = pskl.service.keyboard.Shortcuts.TOOL.STROKE;
this.tooltipDescriptors = [
{key : 'shift', description : 'Hold shift to draw straight lines'}
];
// Stroke's first point coordinates (set in applyToolAt)
this.startCol = null;
@ -40,6 +43,12 @@
ns.Stroke.prototype.moveToolAt = function(col, row, frame, overlay, event) {
overlay.clear();
if (event.shiftKey) {
var coords = this.getStraightLineCoordinates_(col, row);
col = coords.col;
row = coords.row;
}
// When the user moussemove (before releasing), we dynamically compute the
// pixel to draw the line and draw this line in the overlay canvas:
var strokePoints = this.getLinePixels_(this.startCol, col, this.startRow, row);
@ -66,6 +75,13 @@
*/
ns.Stroke.prototype.releaseToolAt = function(col, row, frame, overlay, event) {
var color = this.getToolColor();
if (event.shiftKey) {
var coords = this.getStraightLineCoordinates_(col, row);
col = coords.col;
row = coords.row;
}
// The user released the tool to draw a line. We will compute the pixel coordinate, impact
// the model and draw them in the drawing canvas (not the fake overlay anymore)
var strokePoints = this.getLinePixels_(this.startCol, col, this.startRow, row);
@ -87,4 +103,51 @@
frame.setPixel(pixel.col, pixel.row, replayData.color);
});
};
/**
* Convert col, row to be on the nearest straight line or 45 degrees diagonal.
*/
ns.Stroke.prototype.getStraightLineCoordinates_ = function(col, row) {
// coordinates translated using startCol, startRow as origin
var tCol = col - this.startCol;
var tRow = this.startRow - row;
var dist = Math.sqrt(Math.pow(tCol, 2) + Math.pow(tRow, 2));
var axisDistance = Math.round(dist);
var diagDistance = Math.round(Math.sqrt(Math.pow(dist, 2) / 2));
var PI8 = Math.PI / 8;
var angle = Math.atan2(tRow, tCol);
if (angle < PI8 && angle >= -PI8) {
row = this.startRow;
col = this.startCol + axisDistance;
} else if (angle >= PI8 && angle < 3 * PI8) {
row = this.startRow - diagDistance;
col = this.startCol + diagDistance;
} else if (angle >= 3 * PI8 && angle < 5 * PI8) {
row = this.startRow - axisDistance;
col = this.startCol;
} else if (angle >= 5 * PI8 && angle < 7 * PI8) {
row = this.startRow - diagDistance;
col = this.startCol - diagDistance;
} else if (angle >= 7 * PI8 || angle < -7 * PI8) {
row = this.startRow;
col = this.startCol - axisDistance;
} else if (angle >= -7 * PI8 && angle < -5 * PI8) {
row = this.startRow + diagDistance;
col = this.startCol - diagDistance;
} else if (angle >= -5 * PI8 && angle < -3 * PI8) {
row = this.startRow + axisDistance;
col = this.startCol;
} else if (angle >= -3 * PI8 && angle < -PI8) {
row = this.startRow + diagDistance;
col = this.startCol + diagDistance;
}
return {
col : col,
row : row
};
};
})();