Conditions for prohibiting label creation

To exclude poorly readable labels, parameters in the Do not create labels if group are used.

When applying river labels, created labels follow river contours. If a label falls on a vertical section of the contour, some letters in the curved label become inverted (directed right to left). If the number of inverted letters exceeds the allowable limit, the label is not placed on that contour section. It is recommended to set the value to 50%. Setting the value to 0% means all label letters are oriented left to right or vertically (inverted letters are prohibited). Setting the value to 100% means label letters are oriented along the labeled contour without restrictions. This value can be used when labeling contour line elevations.

If a label section appears right to left, the program analyzes this section. If the deviation from vertical in this section exceeds the Signature deviation from right-to-left is greater than tolerance, the label won't be created. This tolerance limits the creation of simple (straight) inverted right-to-left labels.

If the angle between adjacent letters exceeds the Angle between adjacent letters is greater than tolerance, such a label won't be created. This tolerance excludes labels with intersecting adjacent letters that may be created along river contours with sharp turns.

Overall label curvature can be limited by the The angle between the first letter and the rest is greater tolerance. This parameter reduces the likelihood of creating labels whose letters spiral.

To exclude labeling of short contours, the The length of the line is less parameter is used.