#include "curve-editor.h" #include #define DRAW_RADIUS 5 #define CLICK_RADIUS 8 /* {{{ Types and structures */ typedef enum { MOVE, LINE, CURVE } Operation; static const char * op_to_string (Operation op) { switch (op) { case MOVE: return "move"; case LINE: return "line"; case CURVE: return "curve"; default: g_assert_not_reached (); } } static Operation op_from_string (const char *s) { if (strcmp (s, "move") == 0) return MOVE; else if (strcmp (s, "line") == 0) return LINE; else if (strcmp (s, "curve") == 0) return CURVE; else g_assert_not_reached (); } typedef enum { CUSP, SMOOTH, SYMMETRIC, AUTO } PointType; static const char * point_type_to_string (PointType type) { switch (type) { case CUSP: return "cusp"; case SMOOTH: return "smooth"; case SYMMETRIC: return "symmetric"; case AUTO: return "auto"; default: g_assert_not_reached (); } } static PointType point_type_from_string (const char *s) { if (strcmp (s, "cusp") == 0) return CUSP; else if (strcmp (s, "smooth") == 0) return SMOOTH; else if (strcmp (s, "symmetric") == 0) return SYMMETRIC; else if (strcmp (s, "auto") == 0) return AUTO; else g_assert_not_reached (); } /* We don't store Bezier segments, but an array of points on * the line. Each point comes with its two neighboring control * points, so each Bezier segment contains p[1] and p[2] from * one point, and p[0] and p[1] from the next. * * The control points are irrelevant for MOVE and LINE segments. */ typedef struct { /* 0 and 2 are control points, 1 is the point on the line */ graphene_point_t p[3]; PointType type; gboolean edit; int dragged; int hovered; /* refers to the segment following the point */ Operation op; } PointData; struct _CurveEditor { GtkWidget parent_instance; GArray *points; int dragged; int context; gboolean edit; int molded; GtkWidget *menu; GActionMap *actions; GskStroke *stroke; GdkRGBA color; }; struct _CurveEditorClass { GtkWidgetClass parent_class; }; G_DEFINE_TYPE (CurveEditor, curve_editor, GTK_TYPE_WIDGET) /* }}} */ /* {{{ Misc. geometry */ /* Set q to the projection of p onto the line through a and b */ static void closest_point (const graphene_point_t *p, const graphene_point_t *a, const graphene_point_t *b, graphene_point_t *q) { graphene_vec2_t n; graphene_vec2_t ap; float t; graphene_vec2_init (&n, b->x - a->x, b->y - a->y); graphene_vec2_init (&ap, p->x - a->x, p->y - a->y); t = graphene_vec2_dot (&ap, &n) / graphene_vec2_dot (&n, &n); q->x = a->x + t * (b->x - a->x); q->y = a->y + t * (b->y - a->y); } /* Determine if p is on the line through a and b */ static gboolean collinear (const graphene_point_t *p, const graphene_point_t *a, const graphene_point_t *b) { graphene_point_t q; closest_point (p, a, b, &q); return graphene_point_near (p, &q, 0.0001); } /* Set q to the point on the line through p and a that is * at a distance of d from p, on the opposite side */ static void opposite_point (const graphene_point_t *p, const graphene_point_t *a, float d, graphene_point_t *q) { graphene_vec2_t ap; float t; graphene_vec2_init (&ap, p->x - a->x, p->y - a->y); t = - sqrt (d * d / graphene_vec2_dot (&ap, &ap)); q->x = p->x + t * (a->x - p->x); q->y = p->y + t * (a->y - p->y); } /* Set q to the point on the line through p and a that is * at a distance of d from p, on the same side */ static void scale_point (const graphene_point_t *p, const graphene_point_t *a, float d, graphene_point_t *q) { graphene_vec2_t ap; float t; graphene_vec2_init (&ap, p->x - a->x, p->y - a->y); t = sqrt (d * d / graphene_vec2_dot (&ap, &ap)); q->x = p->x + t * (a->x - p->x); q->y = p->y + t * (a->y - p->y); } /* Set p to the intersection of the lines through a, b * and c, d */ static void line_intersection (const graphene_point_t *a, const graphene_point_t *b, const graphene_point_t *c, const graphene_point_t *d, graphene_point_t *p) { double a1 = b->y - a->y; double b1 = a->x - b->x; double c1 = a1*a->x + b1*a->y; double a2 = d->y - c->y; double b2 = c->x - d->x; double c2 = a2*c->x+ b2*c->y; double det = a1*b2 - a2*b1; if (det == 0) { p->x = NAN; p->y = NAN; } else { p->x = (b2*c1 - b1*c2) / det; p->y = (a1*c2 - a2*c1) / det; } } /* Given 3 points, determine the center of a circle that * passes through all of them. */ static void circle_through_points (const graphene_point_t *a, const graphene_point_t *b, const graphene_point_t *c, graphene_point_t *center) { graphene_point_t ab; graphene_point_t ac; graphene_point_t ab2; graphene_point_t ac2; ab.x = (a->x + b->x) / 2; ab.y = (a->y + b->y) / 2; ac.x = (a->x + c->x) / 2; ac.y = (a->y + c->y) / 2; ab2.x = ab.x + a->y - b->y; ab2.y = ab.y + b->x - a->x; ac2.x = ac.x + a->y - c->y; ac2.y = ac.y + c->x - a->x; line_intersection (&ab, &ab2, &ac, &ac2, center); } /* Return the cosine of the angle between b1 - a and b2 - a */ static double three_point_angle (const graphene_point_t *a, const graphene_point_t *b1, const graphene_point_t *b2) { graphene_vec2_t u; graphene_vec2_t v; graphene_vec2_init (&u, b1->x - a->x, b1->y - a->y); graphene_vec2_init (&v, b2->x - a->x, b2->y - a->y); graphene_vec2_normalize (&u, &u); graphene_vec2_normalize (&v, &v); return graphene_vec2_dot (&u, &v); } /* }}} */ /* {{{ Misc. Bezier math */ /* Given Bezier control points and a t value between 0 and 1, * return new Bezier control points for two segments in left * and right that are obtained by splitting the curve at the * point for t. * * Note that the points in the right array are in returned in * reverse order. */ static void split_bezier (graphene_point_t *points, int length, float t, graphene_point_t *left, int *left_pos, graphene_point_t *right, int *right_pos) { if (length == 1) { left[*left_pos] = points[0]; (*left_pos)++; right[*right_pos] = points[0]; (*right_pos)++; } else { graphene_point_t *newpoints; int i; newpoints = g_alloca (sizeof (graphene_point_t) * (length - 1)); for (i = 0; i < length - 1; i++) { if (i == 0) { left[*left_pos] = points[i]; (*left_pos)++; } if (i + 1 == length - 1) { right[*right_pos] = points[i + 1]; (*right_pos)++; } graphene_point_interpolate (&points[i], &points[i + 1], t, &newpoints[i]); } split_bezier (newpoints, length - 1, t, left, left_pos, right, right_pos); } } static double projection_ratio (double t) { double top, bottom; if (t == 0 || t == 1) return t; top = pow (1 - t, 3), bottom = pow (t, 3) + top; return top / bottom; } static double abc_ratio (double t) { double top, bottom; if (t == 0 || t == 1) return t; bottom = pow (t, 3) + pow (1 - t, 3); top = bottom - 1; return fabs (top / bottom); } static void find_control_points (double t, const graphene_point_t *A, const graphene_point_t *B, const graphene_point_t *C, const graphene_point_t *S, const graphene_point_t *E, graphene_point_t *C1, graphene_point_t *C2) { double angle; double dist; double bc; double de1; double de2; graphene_point_t c; graphene_point_t t0, t1; double tlength; double dx, dy; graphene_point_t e1, e2; graphene_point_t v1, v2; dist = graphene_point_distance (S, E, NULL, NULL); angle = atan2 (E->y - S->y, E->x - S->x) - atan2 (B->y - S->y, B->x - S->x); bc = (angle < 0 || angle > M_PI ? -1 : 1) * dist / 3; de1 = t * bc; de2 = (1 - t) * bc; circle_through_points (S, B, E, &c); t0.x = B->x - (B->y - c.y); t0.y = B->y + (B->x - c.x); t1.x = B->x + (B->y - c.y); t1.y = B->y - (B->x - c.x); tlength = graphene_point_distance (&t0, &t1, NULL, NULL); dx = (t1.x - t0.x) / tlength; dy = (t1.y - t0.y) / tlength; e1.x = B->x + de1 * dx; e1.y = B->y + de1 * dy; e2.x = B->x - de2 * dx; e2.y = B->y - de2 * dy; v1.x = A->x + (e1.x - A->x) / (1 - t); v1.y = A->y + (e1.y - A->y) / (1 - t); v2.x = A->x + (e2.x - A->x) / t; v2.y = A->y + (e2.y - A->y) / t; C1->x = S->x + (v1.x - S->x) / t; C1->y = S->y + (v1.y - S->y) / t; C2->x = E->x + (v2.x - E->x) / (1 - t); C2->y = E->y + (v2.y - E->y) / (1 - t); } /* Given points S, B, E, determine control * points C1, C2 such that B lies on the * Bezier segment given bY S, C1, C2, E. */ static void bezier_through (const graphene_point_t *S, const graphene_point_t *B, const graphene_point_t *E, graphene_point_t *C1, graphene_point_t *C2) { double d1, d2, t; double u, um, s; graphene_point_t A, C; d1 = graphene_point_distance (S, B, NULL, NULL); d2 = graphene_point_distance (E, B, NULL, NULL); t = d1 / (d1 + d2); u = projection_ratio (t); um = 1 - u; C.x = u * S->x + um * E->x; C.y = u * S->y + um * E->y; s = abc_ratio (t); A.x = B->x + (B->x - C.x) / s; A.y = B->y + (B->y - C.y) / s; find_control_points (t, &A, B, &C, S, E, C1, C2); } /* }}} */ /* {{{ Utilities */ static PointData * get_point (CurveEditor *self, int point) { point = point % self->points->len; if (point < 0) point += self->points->len; return &g_array_index (self->points, PointData, point); } static gboolean point_is_visible (CurveEditor *self, int point, int point1) { PointData *pd; if (!self->edit) return FALSE; pd = get_point (self, point); switch (point1) { case 0: if (!pd->edit) return FALSE; else return get_point (self, point - 1)->op == CURVE; case 1: /* point on curve */ return TRUE; case 2: if (!pd->edit) return FALSE; else return pd->op == CURVE; default: g_assert_not_reached (); } } static void maintain_smoothness (CurveEditor *self, int point) { PointData *pd; Operation op, op1; graphene_point_t *p, *c, *c2, *p2; float d; pd = get_point (self, point); if (pd->type == CUSP) return; op = pd->op; op1 = get_point (self, point - 1)->op; p = &pd->p[1]; c = &pd->p[0]; c2 = &pd->p[2]; if (op == CURVE && op1 == CURVE) { d = graphene_point_distance (c, p, NULL, NULL); opposite_point (p, c2, d, c); } else if (op == CURVE && op1 == LINE) { p2 = &get_point (self, point - 1)->p[1]; d = graphene_point_distance (c2, p, NULL, NULL); opposite_point (p, p2, d, c2); } else if (op == LINE && op1 == CURVE) { p2 = &get_point (self, point + 1)->p[1]; d = graphene_point_distance (c, p, NULL, NULL); opposite_point (p, p2, d, c); } } static void maintain_symmetry (CurveEditor *self, int point) { PointData *pd; graphene_point_t *p, *c, *c2; double l1, l2, l; pd = get_point (self, point); if (pd->type != SYMMETRIC) return; c = &pd->p[0]; p = &pd->p[1]; c2 = &pd->p[2]; l1 = graphene_point_distance (p, c, NULL, NULL); l2 = graphene_point_distance (p, c2, NULL, NULL); if (l1 != l2) { l = (l1 + l2) / 2; scale_point (p, c, l, c); scale_point (p, c2, l, c2); } } /* Make the line through the control points perpendicular * to the line bisecting the angle between neighboring * points, and make the lengths 1/3 of the distance to * the corresponding neighboring points. */ static void update_automatic (CurveEditor *self, int point) { PointData *pd, *pd1, *pd2; double l1, l2; graphene_point_t a; pd = get_point (self, point); if (pd->type != AUTO) return; pd1 = get_point (self, point - 1); pd2 = get_point (self, point + 1); l1 = graphene_point_distance (&pd->p[1], &pd1->p[1], NULL, NULL); l2 = graphene_point_distance (&pd->p[1], &pd2->p[1], NULL, NULL); a.x = pd2->p[1].x + (pd->p[1].x - pd1->p[1].x); a.y = pd2->p[1].y + (pd->p[1].y - pd1->p[1].y); scale_point (&pd->p[1], &a, l2/3, &pd->p[2]); opposite_point (&pd->p[1], &a, l1/3, &pd->p[0]); } static void maintain_automatic (CurveEditor *self, int point) { if (get_point (self, point)->op != CURVE || get_point (self, point - 1)->op != CURVE) return; update_automatic (self, point); update_automatic (self, point - 1); update_automatic (self, point + 1); } /* Check if the points arount point currently satisfy * smoothness conditions. Set PointData.type accordingly. */ static void check_smoothness (CurveEditor *self, int point) { Operation op, op1; graphene_point_t *p1, *p2; PointData *pd; pd = get_point (self, point); op = pd->op; op1 = get_point (self, point - 1)->op; if (op == CURVE) p2 = &pd->p[2]; else if (op == LINE) p2 = &get_point (self, point + 1)->p[1]; else p2 = NULL; if (op1 == CURVE) p1 = &pd->p[0]; else if (op1 == LINE) p1 = &get_point (self, point - 1)->p[1]; else p1 = NULL; if (!p1 || !p2 || !collinear (&pd->p[1], p1, p2)) pd->type = CUSP; else pd->type = SMOOTH; } static void insert_point (CurveEditor *self, int point, double pos) { PointData *pd, *pd1, *pd2; graphene_point_t points[4]; PointData np; pd = get_point (self, point); if (pd->op == MOVE) return; pd1 = get_point (self, point + 1); points[0] = pd->p[1]; points[1] = pd->p[2]; points[2] = pd1->p[0]; points[3] = pd1->p[1]; g_array_insert_val (self->points, point + 1, np); pd = get_point (self, point); pd1 = get_point (self, point + 1); pd2 = get_point (self, point + 2); pd1->type = SMOOTH; pd1->hovered = -1; pd1->dragged = -1; if (pd->op == LINE) { pd1->op = LINE; graphene_point_interpolate (&points[0], &points[3], pos, &pd1->p[1]); } else if (pd->op == CURVE) { graphene_point_t left[4]; graphene_point_t right[4]; int left_pos = 0; int right_pos = 0; pd1->op = CURVE; split_bezier (points, 4, pos, left, &left_pos, right, &right_pos); pd->p[1] = left[0]; pd->p[2] = left[1]; pd1->p[0] = left[2]; pd1->p[1] = left[3]; pd1->p[2] = right[2]; pd2->p[0] = right[1]; pd2->p[1] = right[0]; } else g_assert_not_reached (); maintain_smoothness (self, point + 1); maintain_automatic (self, point + 1); gtk_widget_queue_draw (GTK_WIDGET (self)); } static void remove_point (CurveEditor *self, int point) { g_array_remove_index (self->points, point); maintain_smoothness (self, point); maintain_automatic (self, point); } /* }}} */ /* {{{ GskPath helpers */ static void curve_editor_add_segment (CurveEditor *self, GskPathBuilder *builder, int point) { PointData *pd1, *pd; pd1 = get_point (self, point); pd = get_point (self, point + 1); gsk_path_builder_move_to (builder, pd1->p[1].x, pd1->p[1].y); switch (pd1->op) { case LINE: gsk_path_builder_line_to (builder, pd->p[1].x, pd->p[1].y); break; case CURVE: gsk_path_builder_curve_to (builder, pd1->p[2].x, pd1->p[2].y, pd->p[0].x, pd->p[0].y, pd->p[1].x, pd->p[1].y); break; case MOVE: default: break; } } static void curve_editor_add_path (CurveEditor *self, GskPathBuilder *builder) { int i; for (i = 0; i < self->points->len; i++) { PointData *pd1, *pd; pd1 = get_point (self, i); pd = get_point (self, i + 1); if (i == 0) gsk_path_builder_move_to (builder, pd1->p[1].x, pd1->p[1].y); switch (pd1->op) { case MOVE: gsk_path_builder_move_to (builder, pd->p[1].x, pd->p[1].y); break; case LINE: gsk_path_builder_line_to (builder, pd->p[1].x, pd->p[1].y); break; case CURVE: gsk_path_builder_curve_to (builder, pd1->p[2].x, pd1->p[2].y, pd->p[0].x, pd->p[0].y, pd->p[1].x, pd->p[1].y); break; default: g_assert_not_reached (); } } gsk_path_builder_close (builder); } static gboolean find_closest_segment (CurveEditor *self, graphene_point_t *point, float threshold, graphene_point_t *p, int *segment, float *pos) { graphene_point_t pp; float t; int seg; gboolean found = FALSE; int i; for (i = 0; i < self->points->len; i++) { GskPathBuilder *builder; GskPath *path; GskPathMeasure *measure; float t1; graphene_point_t pp1; builder = gsk_path_builder_new (); curve_editor_add_segment (self, builder, i); path = gsk_path_builder_free_to_path (builder); measure = gsk_path_measure_new (path); if (gsk_path_measure_get_closest_point_full (measure, point, threshold, &threshold, &pp1, &t1, NULL)) { seg = i; t = t1 / gsk_path_measure_get_length (measure); pp = pp1; found = TRUE; } gsk_path_measure_unref (measure); gsk_path_unref (path); } if (found) { if (segment) *segment = seg; if (pos) *pos = t; if (p) *p = pp; } return found; } /* }}} */ /* {{{ Drag implementation */ static void drag_begin (GtkGestureDrag *gesture, double start_x, double start_y, CurveEditor *self) { int i, j; graphene_point_t p = GRAPHENE_POINT_INIT (start_x, start_y); float t; int point; if (!self->edit) return; for (i = 0; i < self->points->len; i++) { PointData *pd = get_point (self, i); for (j = 0; j < 3; j++) { if (graphene_point_distance (&pd->p[j], &p, NULL, NULL) < CLICK_RADIUS) { if (point_is_visible (self, i, j)) { self->dragged = i; pd->dragged = j; gtk_widget_queue_draw (GTK_WIDGET (self)); } return; } } } if (find_closest_segment (self, &p, CLICK_RADIUS, NULL, &point, &t)) { /* Can't bend a straight line */ get_point (self, point)->op = CURVE; self->molded = point; return; } gtk_gesture_set_state (GTK_GESTURE (gesture), GTK_EVENT_SEQUENCE_DENIED); } static void drag_control_point (CurveEditor *self, double x, double y) { double dx, dy; graphene_point_t *c, *p, *d; double l1, l2; PointData *pd; pd = get_point (self, self->dragged); d = &pd->p[pd->dragged]; /* before moving the point, record the distances to its neighbors, since * we may want to preserve those */ l1 = graphene_point_distance (&pd->p[1], &pd->p[0], NULL, NULL); l2 = graphene_point_distance (&pd->p[1], &pd->p[2], NULL, NULL); dx = x - d->x; dy = y - d->y; if (pd->dragged == 1) { /* dragged point is on curve */ Operation op, op1, op11, op2; PointData *pd1, *pd2; /* first move the point itself */ d->x = x; d->y = y; /* adjust control points as needed */ pd1 = get_point (self, self->dragged - 1); pd2 = get_point (self, self->dragged + 1); op = pd->op; op1 = pd1->op; op2 = pd2->op; if (op1 == LINE) { /* the other endpoint of the line */ p = &pd1->p[1]; if (op == CURVE && pd->type != CUSP) { /* adjust the control point after the line segment */ opposite_point (d, p, l2, &pd->p[2]); } else { pd->p[2].x += dx; pd->p[2].y += dy; } pd->p[0].x += dx; pd->p[0].y += dy; op11 = get_point (self, self->dragged - 2)->op; if (op11 == CURVE && pd1->type != CUSP) { double l; /* adjust the control point before the line segment */ l = graphene_point_distance (&pd1->p[0], p, NULL, NULL); opposite_point (p, d, l, &pd1->p[0]); } } if (op == LINE) { /* the other endpoint of the line */ p = &pd2->p[1]; if (op1 == CURVE && pd->type != CUSP) { /* adjust the control point before the line segment */ opposite_point (d, p, l1, &pd->p[0]); } else { pd->p[0].x += dx; pd->p[0].y += dy; } pd->p[2].x += dx; pd->p[2].y += dy; if (op2 == CURVE && pd2->type != CUSP) { double l; /* adjust the control point after the line segment */ l = graphene_point_distance (&pd2->p[2], p, NULL, NULL); opposite_point (p, d, l, &pd2->p[2]); } } if (op1 != LINE && op != LINE) { pd->p[0].x += dx; pd->p[0].y += dy; pd->p[2].x += dx; pd->p[2].y += dy; } maintain_automatic (self, self->dragged); } else { /* dragged point is a control point */ graphene_point_t *p1; Operation op, op1; if (pd->dragged == 0) { c = &pd->p[2]; p = &pd->p[1]; op = get_point (self, self->dragged - 1)->op; op1 = get_point (self, self->dragged)->op; p1 = &get_point (self, self->dragged + 1)->p[1]; } else if (pd->dragged == 2) { c = &pd->p[0]; p = &pd->p[1]; op = get_point (self, self->dragged)->op; op1 = get_point (self, self->dragged - 1)->op; p1 = &get_point (self, self->dragged - 1)->p[1]; } else g_assert_not_reached (); if (op == CURVE && pd->type != CUSP) { if (op1 == CURVE) { double l; /* first move the point itself */ d->x = x; d->y = y; /* then adjust the other control point */ if (pd->type == SYMMETRIC) l = graphene_point_distance (d, p, NULL, NULL); else l = graphene_point_distance (c, p, NULL, NULL); opposite_point (p, d, l, c); } else if (op1 == LINE) { graphene_point_t m = GRAPHENE_POINT_INIT (x, y); closest_point (&m, p, p1, d); } else { d->x = x; d->y = y; } } else { d->x = x; d->y = y; } } } static void drag_curve (CurveEditor *self, double x, double y) { PointData *pd, *pd1, *pd2, *pd3; graphene_point_t *S, *E; graphene_point_t B, C1, C2; double l; pd = get_point (self, self->molded); pd1 = get_point (self, self->molded + 1); pd2 = get_point (self, self->molded - 1); pd3 = get_point (self, self->molded + 2); S = &pd->p[1]; B = GRAPHENE_POINT_INIT (x, y); E = &pd1->p[1]; bezier_through (S, &B, E, &C1, &C2); pd->p[2] = C1; pd1->p[0] = C2; /* When the neighboring segments are lines, we can't actually * use C1 and C2 as-is, since we need control points to lie * on the line. So we just use their distance. This makes our * point B not quite match anymore, but we're overconstrained. */ if (pd2->op == LINE) { l = graphene_point_distance (&pd->p[1], &pd->p[2], NULL, NULL); if (three_point_angle (&pd->p[1], &pd2->p[1], &B) > 0) scale_point (&pd->p[1], &pd2->p[1], l, &pd->p[2]); else opposite_point (&pd->p[1], &pd2->p[1], l, &pd->p[2]); } if (pd1->op == LINE) { l = graphene_point_distance (&pd1->p[1], &pd1->p[0], NULL, NULL); if (three_point_angle (&pd1->p[1], &pd3->p[1], &B) > 0) scale_point (&pd1->p[1], &pd3->p[1], l, &pd1->p[0]); else opposite_point (&pd1->p[1], &pd3->p[1], l, &pd1->p[0]); } /* Maintain smoothness and symmetry */ if (pd->type != CUSP) { if (pd->type == SYMMETRIC) l = graphene_point_distance (&pd->p[1], &pd->p[2], NULL, NULL); else l = graphene_point_distance (&pd->p[1], &pd->p[0], NULL, NULL); opposite_point (&pd->p[1], &pd->p[2], l, &pd->p[0]); } if (pd1->type != CUSP) { if (pd1->type == SYMMETRIC) l = graphene_point_distance (&pd1->p[1], &pd1->p[0], NULL, NULL); else l = graphene_point_distance (&pd1->p[1], &pd1->p[2], NULL, NULL); opposite_point (&pd1->p[1], &pd1->p[0], l, &pd1->p[2]); } } static void drag_update (GtkGestureDrag *gesture, double offset_x, double offset_y, CurveEditor *self) { double x, y; gtk_gesture_drag_get_start_point (gesture, &x, &y); x += offset_x; y += offset_y; if (self->dragged != -1) { gtk_gesture_set_state (GTK_GESTURE (gesture), GTK_EVENT_SEQUENCE_CLAIMED); drag_control_point (self, x, y); gtk_widget_queue_draw (GTK_WIDGET (self)); } else if (self->molded != -1) { gtk_gesture_set_state (GTK_GESTURE (gesture), GTK_EVENT_SEQUENCE_CLAIMED); drag_curve (self, x, y); gtk_widget_queue_draw (GTK_WIDGET (self)); } } static void drag_end (GtkGestureDrag *gesture, double offset_x, double offset_y, CurveEditor *self) { drag_update (gesture, offset_x, offset_y, self); self->dragged = -1; self->molded = -1; } /* }}} */ /* {{{ Action callbacks */ static void set_point_type (GSimpleAction *action, GVariant *value, gpointer data) { CurveEditor *self = CURVE_EDITOR (data); get_point (self, self->context)->type = point_type_from_string (g_variant_get_string (value, NULL)); maintain_smoothness (self, self->context); maintain_symmetry (self, self->context); maintain_automatic (self, self->context); gtk_widget_queue_draw (GTK_WIDGET (self)); } static void set_operation (GSimpleAction *action, GVariant *value, gpointer data) { CurveEditor *self = CURVE_EDITOR (data); get_point (self, self->context)->op = op_from_string (g_variant_get_string (value, NULL)); maintain_smoothness (self, self->context); maintain_smoothness (self, self->context + 1); maintain_symmetry (self, self->context); maintain_symmetry (self, self->context + 1); gtk_widget_queue_draw (GTK_WIDGET (self)); } static void remove_current_point (GSimpleAction *action, GVariant *value, gpointer data) { CurveEditor *self = CURVE_EDITOR (data); remove_point (self, self->context); gtk_widget_queue_draw (GTK_WIDGET (self)); } /* }}} */ /* {{{ Event handlers */ static void pressed (GtkGestureClick *gesture, int n_press, double x, double y, CurveEditor *self) { graphene_point_t m = GRAPHENE_POINT_INIT (x, y); int i; int button = gtk_gesture_single_get_current_button (GTK_GESTURE_SINGLE (gesture)); if (!self->edit) return; if (button == GDK_BUTTON_SECONDARY) { for (i = 0; i < self->points->len; i++) { PointData *pd = get_point (self, i); if (graphene_point_distance (&pd->p[1], &m, NULL, NULL) < CLICK_RADIUS) { GAction *action; self->context = i; action = g_action_map_lookup_action (self->actions, "type"); g_simple_action_set_state (G_SIMPLE_ACTION (action), g_variant_new_string (point_type_to_string (pd->type))); action = g_action_map_lookup_action (self->actions, "operation"); g_simple_action_set_state (G_SIMPLE_ACTION (action), g_variant_new_string (op_to_string (pd->op))); gtk_popover_set_pointing_to (GTK_POPOVER (self->menu), &(const GdkRectangle){ x, y, 1, 1 }); gtk_popover_popup (GTK_POPOVER (self->menu)); return; } } } } static void released (GtkGestureClick *gesture, int n_press, double x, double y, CurveEditor *self) { graphene_point_t m = GRAPHENE_POINT_INIT (x, y); int button = gtk_gesture_single_get_current_button (GTK_GESTURE_SINGLE (gesture)); int i; if (!self->edit) return; for (i = 0; i < self->points->len; i++) { PointData *pd = get_point (self, i); if (graphene_point_distance (&pd->p[1], &m, NULL, NULL) < CLICK_RADIUS) { if (button == GDK_BUTTON_PRIMARY) { pd->edit = !pd->edit; gtk_widget_queue_draw (GTK_WIDGET (self)); return; } } } if (button == GDK_BUTTON_PRIMARY) { float t; int point; if (find_closest_segment (self, &m, CLICK_RADIUS, NULL, &point, &t)) { self->dragged = -1; self->molded = -1; insert_point (self, point, t); } } } static void motion (GtkEventControllerMotion *controller, double x, double y, CurveEditor *self) { graphene_point_t m = GRAPHENE_POINT_INIT (x, y); int i, j; gboolean changed = FALSE; if (self->edit) { for (i = 0; i < self->points->len; i++) { PointData *pd = get_point (self, i); int hovered = -1; for (j = 0; j < 3; j++) { if (!point_is_visible (self, i, j)) continue; if (graphene_point_distance (&pd->p[j], &m, NULL, NULL) < CLICK_RADIUS) { hovered = j; break; } } if (pd->hovered != hovered) { pd->hovered = hovered; changed = TRUE; } } } if (changed) gtk_widget_queue_draw (GTK_WIDGET (self)); } static void leave (GtkEventController *controller, CurveEditor *self) { int i; gboolean changed = FALSE; for (i = 0; i < self->points->len; i++) { PointData *pd = get_point (self, i); if (pd->hovered != -1) { pd->hovered = -1; changed = TRUE; } } if (changed) gtk_widget_queue_draw (GTK_WIDGET (self)); } /* }}} */ /* {{{ Snapshot */ static void curve_editor_snapshot (GtkWidget *widget, GtkSnapshot *snapshot) { CurveEditor *self = (CurveEditor *)widget; GskPathBuilder *builder; GskPath *path; GskStroke *stroke; int i, j, k; float width; float height; if (self->points->len == 0) return; width = gtk_widget_get_width (widget); height = gtk_widget_get_width (widget); /* Add the curve itself */ builder = gsk_path_builder_new (); curve_editor_add_path (self, builder); path = gsk_path_builder_free_to_path (builder); gtk_snapshot_push_stroke (snapshot, path, self->stroke); gsk_path_unref (path); gtk_snapshot_append_color (snapshot, &self->color, &GRAPHENE_RECT_INIT (0, 0, width, height )); gtk_snapshot_pop (snapshot); if (self->edit) { /* Add the skeleton */ builder = gsk_path_builder_new (); for (i = 0; i < self->points->len; i++) { PointData *pd = get_point (self, i); gboolean need_move = TRUE; if (point_is_visible (self, i, 0)) { gsk_path_builder_move_to (builder, pd->p[0].x, pd->p[0].y); gsk_path_builder_line_to (builder, pd->p[1].x, pd->p[1].y); need_move = FALSE; } if (point_is_visible (self, i, 2)) { if (need_move) gsk_path_builder_move_to (builder, pd->p[1].x, pd->p[1].y); gsk_path_builder_line_to (builder, pd->p[2].x, pd->p[2].y); } } path = gsk_path_builder_free_to_path (builder); stroke = gsk_stroke_new (1); gtk_snapshot_push_stroke (snapshot, path, stroke); gsk_stroke_free (stroke); gsk_path_unref (path); gtk_snapshot_append_color (snapshot, &(GdkRGBA){ 0, 0, 0, 1 }, &GRAPHENE_RECT_INIT (0, 0, width, height )); gtk_snapshot_pop (snapshot); /* Draw the circles, in several passes, one for each color */ const char *colors[] = { "white", /* hovered */ "red", /* smooth curve points */ "green", /* sharp curve points */ "blue" /* control points */ }; GdkRGBA color; for (k = 0; k < 4; k++) { builder = gsk_path_builder_new (); for (i = 0; i < self->points->len; i++) { PointData *pd = get_point (self, i); for (j = 0; j < 3; j++) { switch (k) { case 0: if (j != pd->hovered) continue; break; case 1: if (j == pd->hovered) continue; if (!(j == 1 && pd->type != CUSP)) continue; break; case 2: if (j == pd->hovered) continue; if (!(j == 1 && pd->type == CUSP)) continue; break; case 3: if (j == pd->hovered) continue; if (j == 1) continue; if (!point_is_visible (self, i, j)) continue; break; default: g_assert_not_reached (); } gsk_path_builder_add_circle (builder, &pd->p[j], DRAW_RADIUS); } } path = gsk_path_builder_free_to_path (builder); gtk_snapshot_push_fill (snapshot, path, GSK_FILL_RULE_WINDING); gdk_rgba_parse (&color, colors[k]); gtk_snapshot_append_color (snapshot, &color, &GRAPHENE_RECT_INIT (0, 0, width, height)); gtk_snapshot_pop (snapshot); stroke = gsk_stroke_new (1.0); gtk_snapshot_push_stroke (snapshot, path, stroke); gsk_stroke_free (stroke); gtk_snapshot_append_color (snapshot, &(GdkRGBA){ 0, 0, 0, 1 }, &GRAPHENE_RECT_INIT (0, 0, width, height)); gtk_snapshot_pop (snapshot); gsk_path_unref (path); } } } /* }}} */ /* {{{ GtkWidget boilerplate */ static void curve_editor_measure (GtkWidget *widget, GtkOrientation orientation, int for_size, int *minimum_size, int *natural_size, int *minimum_baseline, int *natural_baseline) { *minimum_size = 100; *natural_size = 200; } static void curve_editor_size_allocate (GtkWidget *widget, int width, int height, int baseline) { CurveEditor *self = CURVE_EDITOR (widget); gtk_native_check_resize (GTK_NATIVE (self->menu)); } /* }}} */ /* {{{ GObject boilerplate */ static void curve_editor_dispose (GObject *object) { CurveEditor *self = CURVE_EDITOR (object); g_clear_pointer (&self->points, g_array_unref); g_clear_pointer (&self->menu, gtk_widget_unparent); g_clear_object (&self->actions); G_OBJECT_CLASS (curve_editor_parent_class)->dispose (object); } static void curve_editor_class_init (CurveEditorClass *class) { GObjectClass *object_class = G_OBJECT_CLASS (class); GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (class); object_class->dispose = curve_editor_dispose; widget_class->snapshot = curve_editor_snapshot; widget_class->measure = curve_editor_measure; widget_class->size_allocate = curve_editor_size_allocate; } /* }}} */ /* {{{ Setup */ static void curve_editor_init (CurveEditor *self) { GtkEventController *controller; GMenu *menu; GMenu *section; GMenuItem *item; GSimpleAction *action; self->points = g_array_new (FALSE, FALSE, sizeof (PointData)); self->dragged = -1; self->molded = -1; self->edit = FALSE; self->stroke = gsk_stroke_new (1.0); self->color = (GdkRGBA){ 0, 0, 0, 1 }; controller = GTK_EVENT_CONTROLLER (gtk_gesture_drag_new ()); gtk_gesture_single_set_button (GTK_GESTURE_SINGLE (controller), GDK_BUTTON_PRIMARY); g_signal_connect (controller, "drag-begin", G_CALLBACK (drag_begin), self); g_signal_connect (controller, "drag-update", G_CALLBACK (drag_update), self); g_signal_connect (controller, "drag-end", G_CALLBACK (drag_end), self); gtk_widget_add_controller (GTK_WIDGET (self), controller); controller = GTK_EVENT_CONTROLLER (gtk_gesture_click_new ()); gtk_gesture_single_set_button (GTK_GESTURE_SINGLE (controller), 0); g_signal_connect (controller, "pressed", G_CALLBACK (pressed), self); g_signal_connect (controller, "released", G_CALLBACK (released), self); gtk_widget_add_controller (GTK_WIDGET (self), controller); controller = gtk_event_controller_motion_new (); g_signal_connect (controller, "motion", G_CALLBACK (motion), self); g_signal_connect (controller, "leave", G_CALLBACK (leave), self); gtk_widget_add_controller (GTK_WIDGET (self), controller); self->actions = G_ACTION_MAP (g_simple_action_group_new ()); action = g_simple_action_new_stateful ("type", G_VARIANT_TYPE_STRING, g_variant_new_string ("smooth")); g_signal_connect (action, "change-state", G_CALLBACK (set_point_type), self); g_action_map_add_action (G_ACTION_MAP (self->actions), G_ACTION (action)); gtk_widget_insert_action_group (GTK_WIDGET (self), "point", G_ACTION_GROUP (self->actions)); action = g_simple_action_new_stateful ("operation", G_VARIANT_TYPE_STRING, g_variant_new_string ("curve")); g_signal_connect (action, "change-state", G_CALLBACK (set_operation), self); g_action_map_add_action (G_ACTION_MAP (self->actions), G_ACTION (action)); action = g_simple_action_new ("remove", NULL); g_signal_connect (action, "activate", G_CALLBACK (remove_current_point), self); g_action_map_add_action (G_ACTION_MAP (self->actions), G_ACTION (action)); gtk_widget_insert_action_group (GTK_WIDGET (self), "point", G_ACTION_GROUP (self->actions)); menu = g_menu_new (); section = g_menu_new (); item = g_menu_item_new ("Cusp", "point.type::cusp"); g_menu_append_item (section, item); g_object_unref (item); item = g_menu_item_new ("Smooth", "point.type::smooth"); g_menu_append_item (section, item); g_object_unref (item); item = g_menu_item_new ("Symmetric", "point.type::symmetric"); g_menu_append_item (section, item); g_object_unref (item); item = g_menu_item_new ("Automatic", "point.type::auto"); g_menu_append_item (section, item); g_object_unref (item); g_menu_append_section (menu, NULL, G_MENU_MODEL (section)); g_object_unref (section); section = g_menu_new (); item = g_menu_item_new ("Move", "point.operation::move"); g_menu_append_item (section, item); g_object_unref (item); item = g_menu_item_new ("Line", "point.operation::line"); g_menu_append_item (section, item); g_object_unref (item); item = g_menu_item_new ("Curve", "point.operation::curve"); g_menu_append_item (section, item); g_object_unref (item); g_menu_append_section (menu, NULL, G_MENU_MODEL (section)); g_object_unref (section); section = g_menu_new (); item = g_menu_item_new ("Remove", "point.remove"); g_menu_append_item (section, item); g_object_unref (item); g_menu_append_section (menu, NULL, G_MENU_MODEL (section)); g_object_unref (section); self->menu = gtk_popover_menu_new_from_model (G_MENU_MODEL (menu)); g_object_unref (menu); gtk_widget_set_parent (self->menu, GTK_WIDGET (self)); } /* }}} */ /* {{{ API */ GtkWidget * curve_editor_new (void) { return g_object_new (curve_editor_get_type (), NULL); } void curve_editor_set_edit (CurveEditor *self, gboolean edit) { int i; self->edit = edit; if (!self->edit) { for (i = 0; i < self->points->len; i++) { PointData *pd = get_point (self, i); pd->edit = FALSE; pd->hovered = -1; } } gtk_widget_queue_draw (GTK_WIDGET (self)); } static gboolean copy_segments (GskPathOperation op, const graphene_point_t *pts, gsize n_pts, float weight, gpointer data) { CurveEditor *self = data; PointData *pd; PointData *pd1; PointData np; switch (op) { case GSK_PATH_MOVE: if (self->points->len > 0) { pd = &g_array_index (self->points, PointData, self->points->len - 1); pd->op = MOVE; } np.p[1] = pts[0]; g_array_append_val (self->points, np); break; case GSK_PATH_CLOSE: pd = &g_array_index (self->points, PointData, self->points->len - 1); pd1 = &g_array_index (self->points, PointData, 0); if (graphene_point_near (&pd->p[1], &pd1->p[1], 0.001)) { pd1->p[0] = pd->p[0]; g_array_remove_index (self->points, self->points->len - 1); } break; case GSK_PATH_LINE: pd = &g_array_index (self->points, PointData, self->points->len - 1); pd->op = LINE; np.p[1] = pts[1]; g_array_append_val (self->points, np); break; case GSK_PATH_CURVE: pd = &g_array_index (self->points, PointData, self->points->len - 1); pd->op = CURVE; pd->p[2] = pts[1]; np.p[0] = pts[2]; np.p[1] = pts[3]; g_array_append_val (self->points, np); break; case GSK_PATH_CONIC: /* FIXME */ default: g_assert_not_reached (); } return TRUE; } void curve_editor_set_path (CurveEditor *self, GskPath *path) { int i; g_array_set_size (self->points, 0); gsk_path_foreach (path, copy_segments, self); for (i = 0; i < self->points->len; i++) { PointData *pd = get_point (self, i); pd->hovered = -1; pd->dragged = -1; pd->edit= FALSE; check_smoothness (self, i); } gtk_widget_queue_draw (GTK_WIDGET (self)); } GskPath * curve_editor_get_path (CurveEditor *self) { GskPathBuilder *builder; builder = gsk_path_builder_new (); curve_editor_add_path (self, builder); return gsk_path_builder_free_to_path (builder); } void curve_editor_set_stroke (CurveEditor *self, GskStroke *stroke) { gsk_stroke_free (self->stroke); self->stroke = gsk_stroke_copy (stroke); gtk_widget_queue_draw (GTK_WIDGET (self)); } const GskStroke * curve_editor_get_stroke (CurveEditor *self) { return self->stroke; } void curve_editor_set_color (CurveEditor *self, GdkRGBA *color) { self->color = *color; gtk_widget_queue_draw (GTK_WIDGET (self)); } const GdkRGBA * curve_editor_get_color (CurveEditor *self) { return &self->color; } /* }}} */ /* vim:set foldmethod=marker expandtab: */