Geometry

Libembroidery 1.0.0-alpha https://www.libembroidery.org

A library for reading, writing, altering and otherwise processing machine embroidery files and designs.

Also, the core library supporting the Embroidermodder Project’s family of machine embroidery interfaces.

Copyright 2018-2025 The Embroidermodder Team Licensed under the terms of the zlib license.

Only uses source from this directory or standard C libraries, not including POSIX headers like unistd since this library needs to support non-POSIX systems like Windows.

The Geometry System

Functions

EmbVector emb_vector(EmbReal x, EmbReal y)

Create an EmbVector from data.

EmbVector emb_vector_normalize(EmbVector vector)

Finds the unit length vector a result in the same direction as a vector.

EmbVector emb_vector_scale(EmbVector vector, EmbReal magnitude)

The scalar multiple a magnitude of a vector. Returned as a vector.

EmbVector emb_vector_add(EmbVector a, EmbVector b)

The sum of two vectors returned as a vector.

EmbVector emb_vector_average(EmbVector a, EmbVector b)

The average of two vectors returned as a vector.

EmbVector emb_vector_subtract(EmbVector v1, EmbVector v2)

The difference between two vectors returned as a result.

EmbReal emb_vector_dot(EmbVector a, EmbVector b)

The dot product of two vectors returned as a EmbReal.

EmbReal emb_vector_cross(EmbVector a, EmbVector b)

The “cross product” as vectors a and b returned as a real value.

Technically, this is the magnitude of the cross product when the embroidery is placed in the z=0 plane (since the cross product is defined for 3-dimensional vectors).

EmbVector emb_vector_transpose_product(EmbVector v1, EmbVector v2)

Since we aren’t using full 3D vector algebra here, all vectors are “vertical”. so this is like the product v1^{T} I_{2} v2 for our vectors a v1 and v2 so a “component-wise product”. The result is stored at the pointer a result.

EmbReal emb_vector_length(EmbVector vector)

The length or absolute value of the vector a vector.

EmbReal emb_vector_relativeX(EmbVector a1, EmbVector a2, EmbVector a3)

EmbReal emb_vector_relativeY(EmbVector a1, EmbVector a2, EmbVector a3)

EmbReal emb_vector_angle(EmbVector v)

EmbVector emb_vector_unit(EmbReal alpha)

The unit vector in the direction a angle.

EmbReal emb_vector_distance(EmbVector a, EmbVector b)

void emb_geometry_move(EmbGeometry *obj, EmbVector delta)

int emb_approx(EmbVector point1, EmbVector point2)

EmbReal emb_apothem(EmbGeometry *g, int *error)

EmbReal emb_sagitta(EmbGeometry *g, int *error)

EmbVector emb_start(EmbGeometry *g, int *error)

EmbVector emb_end(EmbGeometry *g, int *error)

EmbReal emb_width(EmbGeometry *g, int *error)

EmbReal emb_height(EmbGeometry *g, int *error)

EmbReal emb_radius(EmbGeometry *g, int *error)

EmbReal emb_radius_major(EmbGeometry *g, int *error)

EmbReal emb_radius_minor(EmbGeometry *g, int *error)

EmbReal emb_diameter_major(EmbGeometry *g, int *error)

EmbReal emb_diameter_minor(EmbGeometry *g, int *error)

EmbReal emb_diameter(EmbGeometry *g, int *error)

EmbVector emb_quadrant(EmbGeometry *geometry, int degrees, int *error)

EmbReal emb_angle(EmbGeometry *geometry, int *error)

EmbReal emb_start_angle(EmbGeometry *geometry, int *error)

EmbReal emb_end_angle(EmbGeometry *geometry, int *error)

EmbReal emb_arc_length(EmbGeometry *g, int *error)

EmbReal emb_area(EmbGeometry *g, int *error)

EmbVector emb_center(EmbGeometry *g, int *error)

EmbVector emb_chord(EmbGeometry *g, int *error)

EmbReal emb_included_angle(EmbGeometry *g, int *error)

char emb_clockwise(EmbGeometry *geometry, int *error)

int emb_set_start_angle(EmbGeometry *geometry, EmbReal angle)

int emb_set_end_angle(EmbGeometry *geometry, EmbReal angle)

int emb_set_start_point(EmbGeometry *geometry, EmbVector point)

int emb_set_mid_point(EmbGeometry *geometry, EmbVector point)

int emb_set_end_point(EmbGeometry *geometry, EmbVector point)

int emb_set_radius(EmbGeometry *g, EmbReal radius)

int emb_set_diameter(EmbGeometry *geometry, EmbReal diameter)

int emb_set_area(EmbGeometry *geometry, EmbReal area)

int emb_set_circumference(EmbGeometry *geometry, EmbReal circumference)

int emb_set_radius_major(EmbGeometry *geometry, EmbReal radius)

int emb_set_radius_minor(EmbGeometry *geometry, EmbReal radius)

int emb_set_diameter_major(EmbGeometry *geometry, EmbReal diameter)

int emb_set_diameter_minor(EmbGeometry *geometry, EmbReal diameter)

EmbReal emb_circumference(EmbGeometry *geometry, int *error)

EmbGeometry *emb_init(int type_in)

void emb_free(EmbGeometry *obj)

EmbRect emb_boundingRect(EmbGeometry *obj)

EmbGeometry emb_arc(EmbReal x1, EmbReal y1, EmbReal x2, EmbReal y2, EmbReal x3, EmbReal y3)

char emb_arc_clockwise(EmbGeometry g)

int emb_set_center(EmbGeometry *g, EmbVector point)

void emb_set_color(EmbGeometry *obj, EmbColor color)

void emb_set_color_rgb(EmbGeometry *obj, unsigned int rgb)

void emb_set_linetype(EmbGeometry *obj, int lineType)

void emb_set_line_weight(EmbGeometry *obj, float lineWeight)

EmbVector emb_base_rubber_point(EmbGeometry *obj, const char *key)

const char *emb_base_rubber_text(EmbGeometry *obj, const char *key)

void emb_circle_main(void)

void emb_circle_set_area(EmbCircle *circle, float area)

void emb_ellipse_main(void)

EmbVector embRect_bottomLeft(EmbRect rect)

EmbVector embRect_bottomRight(EmbRect rect)

EmbGeometry emb_circle(EmbReal x, EmbReal y, EmbReal radius)

int getCircleCircleIntersections(EmbCircle c0, EmbCircle c1, EmbVector *p0, EmbVector *p1)

int getCircleTangentPoints(EmbCircle c, EmbVector point, EmbVector *t0, EmbVector *t1)

EmbEllipse emb_ellipse_init(void)

EmbReal emb_ellipse_diameterX(EmbEllipse ellipse)

EmbReal emb_ellipse_diameterY(EmbEllipse ellipse)

void emb_ellipse_setSize(float width, float height)

int emb_round(EmbReal x)

EmbReal radians(EmbReal degree)

EmbReal degrees(EmbReal radian)

EmbVector emb_line_normalVector(EmbLine line, int clockwise)

EmbVector emb_line_toVector(EmbLine line)

EmbVector emb_line_intersectionPoint(EmbLine line1, EmbLine line2, int *emb_error)

EmbRect emb_rect(EmbReal x, EmbReal y, EmbReal w, EmbReal h)

void textSingle_setJustify(EmbGeometry *g, const char *justify)

int emb_backwards(EmbGeometry *g, int *error)

int emb_bold(EmbGeometry *g, int *error)

int emb_bulge(EmbGeometry *g, int *error)

EmbReal emb_chord_length(EmbGeometry *g, int *error)

Variables

EmbReal epsilon

const char *justify_options[] = {"Left", "Center", "Right", "Aligned", "Middle", "Fit", "Top Left", "Top Center", "Top Right", "Middle Left", "Middle Center", "Middle Right", "Bottom Left", "Bottom Center", "Bottom Right", END_SYMBOL}