circuitpython/shared-module/vectorio/Polygon.c

191 lines
6.5 KiB
C

#include "shared-module/vectorio/__init__.h"
#include "shared-bindings/vectorio/Polygon.h"
#include "shared-module/displayio/area.h"
#include "py/runtime.h"
#include "py/gc.h"
#include "stdlib.h"
#include <stdio.h>
#define VECTORIO_POLYGON_DEBUG(...) (void)0
// #define VECTORIO_POLYGON_DEBUG(...) mp_printf(&mp_plat_print, __VA_ARGS__)
// Converts a list of points tuples to a flat list of ints for speedier internal use.
// Also validates the points.
static void _clobber_points_list(vectorio_polygon_t *self, mp_obj_t points_tuple_list) {
size_t len = 0;
mp_obj_t *items;
mp_obj_list_get(points_tuple_list, &len, &items);
VECTORIO_POLYGON_DEBUG(" self.len: %d, len: %d, ", self->len, len);
if (len < 3) {
mp_raise_TypeError_varg(translate("Polygon needs at least 3 points"));
}
if (self->len < 2 * len) {
if (self->points_list != NULL) {
VECTORIO_POLYGON_DEBUG("free(%d), ", sizeof(self->points_list));
gc_free(self->points_list);
}
self->points_list = gc_alloc(2 * len * sizeof(uint16_t), false, false);
VECTORIO_POLYGON_DEBUG("alloc(%p, %d)", self->points_list, 2 * len * sizeof(uint16_t));
}
self->len = 2 * len;
for (uint16_t i = 0; i < len; ++i) {
size_t tuple_len = 0;
mp_obj_t *tuple_items;
mp_obj_tuple_get(items[i], &tuple_len, &tuple_items);
if (tuple_len != 2) {
mp_raise_ValueError_varg(translate("%q must be a tuple of length 2"), MP_QSTR_point);
}
mp_int_t x;
mp_int_t y;
if (!mp_obj_get_int_maybe(tuple_items[ 0 ], &x)
|| !mp_obj_get_int_maybe(tuple_items[ 1 ], &y)
|| x < SHRT_MIN || x > SHRT_MAX || y < SHRT_MIN || y > SHRT_MAX
) {
gc_free(self->points_list);
self->points_list = NULL;
mp_raise_ValueError_varg(translate("unsupported %q type"), MP_QSTR_point);
self->len = 0;
}
self->points_list[2 * i ] = (int16_t)x;
self->points_list[2 * i + 1] = (int16_t)y;
}
}
void common_hal_vectorio_polygon_construct(vectorio_polygon_t *self, mp_obj_t points_list) {
VECTORIO_POLYGON_DEBUG("%p polygon_construct: ", self);
self->points_list = NULL;
self->len = 0;
self->on_dirty.obj = NULL;
_clobber_points_list(self, points_list);
VECTORIO_POLYGON_DEBUG("\n");
}
mp_obj_t common_hal_vectorio_polygon_get_points(vectorio_polygon_t *self) {
VECTORIO_POLYGON_DEBUG("%p common_hal_vectorio_polygon_get_points {len: %d, points_list: %p}\n", self, self->len, self->points_list);
mp_obj_list_t *list = MP_OBJ_TO_PTR(mp_obj_new_list(0, NULL));
VECTORIO_POLYGON_DEBUG(" >points\n");
for (uint16_t i = 0; i < self->len; i += 2) {
VECTORIO_POLYGON_DEBUG(" (%4d, %4d)\n", self->points_list[i], self->points_list[i + 1]);
mp_obj_tuple_t *pair = MP_OBJ_TO_PTR(mp_obj_new_tuple(2, NULL));
pair->items[0] = mp_obj_new_int((mp_int_t)self->points_list[i ]);
pair->items[1] = mp_obj_new_int((mp_int_t)self->points_list[i + 1]);
mp_obj_list_append(
list,
pair
);
}
VECTORIO_POLYGON_DEBUG(" <points\n");
return MP_OBJ_FROM_PTR(list);
}
void common_hal_vectorio_polygon_set_points(vectorio_polygon_t *self, mp_obj_t points_list) {
VECTORIO_POLYGON_DEBUG("%p common_hal_vectorio_polygon_set_points: ", self);
_clobber_points_list(self, points_list);
if (self->on_dirty.obj != NULL) {
self->on_dirty.event(self->on_dirty.obj);
}
VECTORIO_POLYGON_DEBUG("\n");
}
void common_hal_vectorio_polygon_set_on_dirty(vectorio_polygon_t *self, vectorio_event_t notification) {
if (self->on_dirty.obj != NULL) {
mp_raise_TypeError(translate("polygon can only be registered in one parent"));
}
self->on_dirty = notification;
}
void common_hal_vectorio_polygon_get_area(void *polygon, displayio_area_t *area) {
vectorio_polygon_t *self = polygon;
VECTORIO_POLYGON_DEBUG("%p common_hal_vectorio_polygon_get_area\n");
area->x1 = SHRT_MAX;
area->y1 = SHRT_MAX;
area->x2 = SHRT_MIN;
area->y2 = SHRT_MIN;
for (uint16_t i = 0; i < self->len; ++i) {
int16_t x = self->points_list[i];
++i;
int16_t y = self->points_list[i];
if (x < area->x1) {
VECTORIO_POLYGON_DEBUG(" x1: %d\n", x);
area->x1 = x;
}
if (y < area->y1) {
VECTORIO_POLYGON_DEBUG(" y1: %d\n", y);
area->y1 = y;
}
if (x > area->x2) {
VECTORIO_POLYGON_DEBUG(" x2: %d\n", x);
area->x2 = x;
}
if (y > area->y2) {
VECTORIO_POLYGON_DEBUG(" y2: %d\n", y);
area->y2 = y;
}
}
}
// <0 if the point is to the left of the line vector
// 0 if the point is on the line
// >0 if the point is to the right of the line vector
__attribute__((always_inline)) static inline int line_side(int16_t x1, int16_t y1, int16_t x2, int16_t y2, int16_t px, int16_t py) {
return (px - x1) * (y2 - y1)
- (py - y1) * (x2 - x1);
}
uint32_t common_hal_vectorio_polygon_get_pixel(void *obj, int16_t x, int16_t y) {
VECTORIO_POLYGON_DEBUG("%p polygon get_pixel %d, %d\n", obj, x, y);
vectorio_polygon_t *self = obj;
if (self->len == 0) {
return 0;
}
int16_t winding_number = 0;
int16_t x1 = self->points_list[0];
int16_t y1 = self->points_list[1];
for (uint16_t i = 2; i <= self->len + 1; ++i) {
VECTORIO_POLYGON_DEBUG(" {(%3d, %3d),", x1, y1);
int16_t x2 = self->points_list[i % self->len];
++i;
int16_t y2 = self->points_list[i % self->len];
VECTORIO_POLYGON_DEBUG(" (%3d, %3d)}\n", x2, y2);
if (y1 <= y) {
if (y2 > y && line_side(x1, y1, x2, y2, x, y) < 0) {
// Wind up, point is to the left of the edge vector
++winding_number;
VECTORIO_POLYGON_DEBUG(" wind:%2d winding_number:%2d\n", 1, winding_number);
}
} else if (y2 <= y && line_side(x1, y1, x2, y2, x, y) > 0) {
// Wind down, point is to the right of the edge vector
--winding_number;
VECTORIO_POLYGON_DEBUG(" wind:%2d winding_number:%2d\n", -1, winding_number);
}
x1 = x2;
y1 = y2;
}
return winding_number == 0 ? 0 : 1;
}
mp_obj_t common_hal_vectorio_polygon_get_draw_protocol(void *polygon) {
vectorio_polygon_t *self = polygon;
return self->draw_protocol_instance;
}