Add place for examples

and fix some bugs that make the examples not work!

1 files changed, 115 insertions, 0 deletions

diff --git a/examples/stacked.c b/examples/stacked.c
new file mode 100644
index 0000000..256a682
--- /dev/null
+++ b/examples/stacked.c
@@ -0,0 +1,115 @@
+#include "cad.h"
+
+struct box {
+	struct component corner[4];
+	struct component side[4];
+};
+
+void a_box(struct box *box, struct topology *topo, struct constraints *constr) {
+	assert(box != NULL);
+
+	*box = (struct box){
+		.corner = {
+			{.type = COM_POINT},
+			{.type = COM_POINT},
+			{.type = COM_POINT},
+			{.type = COM_POINT},
+		},
+		.side = {
+			{.type = COM_LINE},
+			{.type = COM_LINE},
+			{.type = COM_LINE},
+			{.type = COM_LINE},
+		},
+	};
+
+	if(topo != NULL) {
+		add_fragment(topo, (struct topology_elem[]){
+			TOPO_MOVETO(&box->corner[0]),
+			TOPO_LINETO(&box->corner[1]),
+			TOPO_LINETO(&box->corner[2]),
+			TOPO_LINETO(&box->corner[3]),
+			TOPO_LINETO(&box->corner[0]),
+
+			TOPO_END(),
+		});
+	}
+
+	if(constr != NULL) {
+		add_constraint(constr, (struct constraint[]){
+			POINT_ON_LINE(&box->corner[0], &box->side[0]),
+			POINT_ON_LINE(&box->corner[1], &box->side[0]),
+
+			POINT_ON_LINE(&box->corner[1], &box->side[1]),
+			POINT_ON_LINE(&box->corner[2], &box->side[1]),
+
+			POINT_ON_LINE(&box->corner[2], &box->side[2]),
+			POINT_ON_LINE(&box->corner[3], &box->side[2]),
+
+			POINT_ON_LINE(&box->corner[0], &box->side[3]),
+			POINT_ON_LINE(&box->corner[3], &box->side[3]),
+
+			LL_ANGLE(&box->side[3], &box->side[0], DEG(90)),
+			LL_ANGLE(&box->side[1], &box->side[2], DEG(90)),
+			LL_ANGLE(&box->side[2], &box->side[3], DEG(90)),
+			CEND(),
+		});
+	}
+}
+
+void draw_from_constraints(struct constraints *c, struct topology *t, struct canvas *cv) {
+	struct drawing drawing = {};
+	bool rc = solve_constraints(c, &drawing);
+	assert(rc);
+
+	// Copy over all the parameter values to a new array
+	// @PERF: Maybe we should just store them in a separate array to start with
+	double *params = malloc(sizeof(double) * (c->length));
+	for(size_t i = 0; i < c->length; i++) {
+		params[i] = c->elements[i].v;
+	}
+
+	place_points(&drawing, params);
+	free(params);
+
+	begin_drawing(cv);
+	draw_topology(cv, t);
+	draw_constraints(cv, c);
+	end_drawing(cv);
+}
+
+int main(int argc, char *argv[]) {
+	struct constraints constraints = {};
+	struct topology topo = {};
+
+	struct box box1;
+	a_box(&box1, &topo, &constraints);
+
+	struct box box2;
+	a_box(&box2, &topo, &constraints);
+
+	struct box box3;
+	a_box(&box3, &topo, &constraints);
+
+	add_constraint(&constraints, (struct constraint[]){
+		PP_DISTANCE(&box1.corner[0], &box1.corner[1], 10),
+		PP_DISTANCE(&box1.corner[1], &box1.corner[2], 10),
+
+		PP_SAME(&box2.corner[0], &box1.corner[3]),
+		PP_SAME(&box2.corner[1], &box1.corner[2]),
+		PP_DISTANCE(&box2.corner[1], &box2.corner[2], 10),
+
+		PP_SAME(&box3.corner[0], &box2.corner[3]),
+		PP_DISTANCE(&box3.corner[1], &box3.corner[2], 10),
+		PP_DISTANCE(&box3.corner[0], &box3.corner[1], 7),
+		LL_ANGLE(&box3.side[0], &box1.side[0], DEG(-40)),
+		CEND(),
+	});
+
+	struct canvas canvas = {
+		.state = CANVAS_INIT,
+		.f = stdout,
+	};
+	
+	draw_from_constraints(&constraints, &topo, &canvas);
+}