struct cxt *cxt = user_data;
struct graph_point *p3 = data;
if(cxt->p0 != NULL) {
- double p1_x = (p3->x - cxt->p0->x)/3.0;
- double p1_y = (p3->y - cxt->p0->y)/3.0;
- double p2_x = (p3->x + 2*cxt->p0->x)/3.0;
- double p2_y = (p3->y + 2*cxt->p0->y)/3.0;
+ double p1_x = (p3->x + 2*cxt->p0->x)/3.0;
+ double p1_y = (p3->y + 2*cxt->p0->y)/3.0;
+ double p2_x = (2*p3->x + cxt->p0->x)/3.0;
+ double p2_y = (2*p3->y + cxt->p0->y)/3.0;
graph_add_line(cxt->graph, cxt->p0->x, cxt->p0->y, p1_x, p1_y, p2_x, p2_y, p3->x, p3->y);
}
cxt->p0 = p3;
cxt.p0 = NULL;
g_ptr_array_foreach(graph->points, &linear_interpolate, &cxt);
}
+
+void graph_bezier_linear_to_cubic(double x0, double x3, double *x1, double *x2) {
+ *x1 = (x3 + 2.0*x0)/3.0;
+ *x2 = (2.0*x3 + x0)/3.0;
+}
+
+void graph_bezier_qudratic_to_cubic(double x0, double x3, double *x1, double *x2) {
+ *x2 = (x3 - x0)/3.0 + (*x1);
+ *x1 = (x0 - 3.0*(*x1))/2.0;
+}