 # 19.145 draw:enhanced-path - issues with definition of behavior

XMLWordPrintable

#### Details

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: None
• Fix Version/s:
• Component/s: None
• Labels:
None
• Proposal:
Hide

Command T

Name angle-ellipseto

Parameters (x y wR hR t0 t1) +

Description

Draws a line from the current point to the start point of an arc of an ellipse and then draws the arc itself. The ellipse is given by the center(x, y), the width 2*wR, and the height 2*hR.

The arc is specified by the start-angle t0 in degrees and end-angle t1 in degrees. The angles may be of any value, but are used modulo 360° with range 0° <= angle < 360° to get start and end point of the arc. The angles specify radial vectors. The start and end point of the arc are the intersection of these vectors with the ellipse. In case the start point equals the end point, only in case |t1 − t0| = 360° a full ellipse is drawn, otherwise an arc of 0° central angle is drawn. The orientation of the angles is the same as in command G, see figure nnn.

The arc is drawn clockwise.

The end point becomes the new current point at the end of the command.

Command U

Name angle-ellipse

Parameters (x y wR hR t0 t1) +

Description

The same as the “T” command, except that no current point is required but an implicit moveto to the start point is done and thus no line to the start point is drawn.

Show
Command T Name angle-ellipseto Parameters (x y wR hR t0 t1) + Description Draws a line from the current point to the start point of an arc of an ellipse and then draws the arc itself. The ellipse is given by the center(x, y), the width 2*wR, and the height 2*hR. The arc is specified by the start-angle t0 in degrees and end-angle t1 in degrees. The angles may be of any value, but are used modulo 360° with range 0° <= angle < 360° to get start and end point of the arc. The angles specify radial vectors. The start and end point of the arc are the intersection of these vectors with the ellipse. In case the start point equals the end point, only in case |t1 − t0| = 360° a full ellipse is drawn, otherwise an arc of 0° central angle is drawn. The orientation of the angles is the same as in command G, see figure nnn. The arc is drawn clockwise. The end point becomes the new current point at the end of the command.   Command U Name angle-ellipse Parameters (x y wR hR t0 t1) + Description The same as the “T” command, except that no current point is required but an implicit moveto to the start point is done and thus no line to the start point is drawn.

#### Description

The word "segment of ellipse" is misleading. No application draws a segment, but all draw an arc, and in case of filling, a filling in shape of a sector.

The meaning of the angles it not clear. Examples: t0=0, t1=360 generates a full ellipse in applications. What rendering is expected for t0=-10, t1=350 (negative values), or for t0=350, t1=240 (start > end), of for t0=30, t1=480 (difference > 360) ?

#### People

• Assignee: Unassigned
Reporter: Patrick Durusau
• Watchers:
2 Start watching this issue

#### Dates

• Created:
Updated:
Resolved: