Add function for drawing polygons to bitmaptools

Author: matemaciek

locale/circuitpython.pot

@@ -814,6 +814,14 @@ msgid ""
 "connection."
 msgstr ""
 
+#: shared-bindings/bitmaptools/__init__.c
+msgid "Coordinate arrays have different lengths"
+msgstr ""
+
+#: shared-bindings/bitmaptools/__init__.c
+msgid "Coordinate arrays types have different sizes"
+msgstr ""
+
 #: py/persistentcode.c
 msgid "Corrupt .mpy file"
 msgstr ""

shared-bindings/bitmaptools/__init__.c

@@ -522,6 +522,69 @@ STATIC mp_obj_t bitmaptools_obj_draw_line(size_t n_args, const mp_obj_t *pos_arg
 MP_DEFINE_CONST_FUN_OBJ_KW(bitmaptools_draw_line_obj, 0, bitmaptools_obj_draw_line);
 // requires all 6 arguments
 
+//| def draw_polygon(
+//|     dest_bitmap: displayio.Bitmap,
+//|     xs: ReadableBuffer,
+//|     ys: ReadableBuffer,
+//|     value: int,
+//|     close: Optional[bool] = True,
+//| ) -> None:
+//|     """Draw a polygon conecting points on provided bitmap with provided value
+//|
+//|     :param bitmap dest_bitmap: Destination bitmap that will be written into
+//|     :param int xs: x-pixel position of the polygon's vertices
+//|     :param int ys: y-pixel position of the polygon's vertices
+//|     :param int value: Bitmap palette index that will be written into the
+//|            line in the destination bitmap
+//|     :param bool close: (Optional) Wether to connect first and last point. (True)
+//|     """
+//|     ...
+//|
+STATIC mp_obj_t bitmaptools_obj_draw_polygon(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
+    enum {ARG_dest_bitmap, ARG_xs, ARG_ys, ARG_value, ARG_close};
+
+    static const mp_arg_t allowed_args[] = {
+        {MP_QSTR_dest_bitmap, MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL}},
+        {MP_QSTR_xs, MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL}},
+        {MP_QSTR_ys, MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL}},
+        {MP_QSTR_value, MP_ARG_REQUIRED | MP_ARG_INT, {.u_obj = MP_OBJ_NULL}},
+        {MP_QSTR_close, MP_ARG_BOOL, {.u_bool = true}},
+    };
+    mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
+    mp_arg_parse_all(n_args, pos_args, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
+
+    displayio_bitmap_t *destination = MP_OBJ_TO_PTR(args[ARG_dest_bitmap].u_obj);     // the destination bitmap
+
+    mp_buffer_info_t xs_buf, ys_buf;
+    mp_get_buffer_raise(args[ARG_xs].u_obj, &xs_buf, MP_BUFFER_READ);
+    mp_get_buffer_raise(args[ARG_ys].u_obj, &ys_buf, MP_BUFFER_READ);
+    size_t xs_size = mp_binary_get_size('@', xs_buf.typecode, NULL);
+    size_t ys_size = mp_binary_get_size('@', ys_buf.typecode, NULL);
+    size_t xs_len = xs_buf.len / xs_size;
+    size_t ys_len = ys_buf.len / ys_size;
+    if (xs_size != ys_size) {
+        mp_raise_ValueError(translate("Coordinate arrays types have different sizes"));
+    }
+    if (xs_len != ys_len) {
+        mp_raise_ValueError(translate("Coordinate arrays have different lengths"));
+    }
+
+    uint32_t value, color_depth;
+    value = args[ARG_value].u_int;
+    color_depth = (1 << destination->bits_per_value);
+    if (color_depth <= value) {
+        mp_raise_ValueError(translate("out of range of target"));
+    }
+
+    bool close = args[ARG_close].u_bool;
+
+    common_hal_bitmaptools_draw_polygon(destination, xs_buf.buf, ys_buf.buf, xs_len, xs_size, value, close);
+
+    return mp_const_none;
+}
+
+MP_DEFINE_CONST_FUN_OBJ_KW(bitmaptools_draw_polygon_obj, 0, bitmaptools_obj_draw_polygon);
+
 //| def arrayblit(
 //|     bitmap: displayio.Bitmap,
 //|     data: ReadableBuffer,
@@ -783,6 +846,7 @@ STATIC const mp_rom_map_elem_t bitmaptools_module_globals_table[] = {
     { MP_ROM_QSTR(MP_QSTR_fill_region), MP_ROM_PTR(&bitmaptools_fill_region_obj) },
     { MP_ROM_QSTR(MP_QSTR_boundary_fill), MP_ROM_PTR(&bitmaptools_boundary_fill_obj) },
     { MP_ROM_QSTR(MP_QSTR_draw_line), MP_ROM_PTR(&bitmaptools_draw_line_obj) },
+    { MP_ROM_QSTR(MP_QSTR_draw_polygon), MP_ROM_PTR(&bitmaptools_draw_polygon_obj) },
     { MP_ROM_QSTR(MP_QSTR_dither), MP_ROM_PTR(&bitmaptools_dither_obj) },
     { MP_ROM_QSTR(MP_QSTR_DitherAlgorithm), MP_ROM_PTR(&bitmaptools_dither_algorithm_type) },
 };

shared-bindings/bitmaptools/__init__.h

@@ -64,6 +64,7 @@ void common_hal_bitmaptools_draw_line(displayio_bitmap_t *destination,
     int16_t x1, int16_t y1,
     uint32_t value);
 
+void common_hal_bitmaptools_draw_polygon(displayio_bitmap_t *destination, void *xs, void *ys, size_t points_len, int point_size, uint32_t value, bool close);
 void common_hal_bitmaptools_readinto(displayio_bitmap_t *self, mp_obj_t *file, int element_size, int bits_per_pixel, bool reverse_pixels_in_word, bool swap_bytes, bool reverse_rows);
 void common_hal_bitmaptools_arrayblit(displayio_bitmap_t *self, void *data, int element_size, int x1, int y1, int x2, int y2, bool skip_specified, uint32_t skip_index);
 void common_hal_bitmaptools_dither(displayio_bitmap_t *dest_bitmap, displayio_bitmap_t *source_bitmap, displayio_colorspace_t colorspace, bitmaptools_dither_algorithm_t algorithm);

shared-module/bitmaptools/__init__.c

@@ -384,37 +384,11 @@ void common_hal_bitmaptools_boundary_fill(displayio_bitmap_t *destination,
 
 }
 
-void common_hal_bitmaptools_draw_line(displayio_bitmap_t *destination,
+STATIC void draw_line(displayio_bitmap_t *destination,
     int16_t x0, int16_t y0,
     int16_t x1, int16_t y1,
     uint32_t value) {
 
-    //
-    // adapted from Adafruit_CircuitPython_Display_Shapes.Polygon._line
-    //
-
-    // update the dirty rectangle
-    int16_t xbb0, xbb1, ybb0, ybb1;
-    if (x0 < x1) {
-        xbb0 = x0;
-        xbb1 = x1 + 1;
-    } else {
-        xbb0 = x1;
-        xbb1 = x0 + 1;
-    }
-    if (y0 < y1) {
-        ybb0 = y0;
-        ybb1 = y1 + 1;
-    } else {
-        ybb0 = y1;
-        ybb1 = y0 + 1;
-    }
-    displayio_area_t area = { xbb0, ybb0, xbb1, ybb1, NULL };
-    displayio_area_t bitmap_area = { 0, 0, destination->width, destination->height, NULL };
-    displayio_area_compute_overlap(&area, &bitmap_area, &area);
-
-    displayio_bitmap_set_dirty_area(destination, &area);
-
     int16_t temp, x, y;
 
     if (x0 == x1) { // vertical line
@@ -488,6 +462,84 @@ void common_hal_bitmaptools_draw_line(displayio_bitmap_t *destination,
     }
 }
 
+void common_hal_bitmaptools_draw_line(displayio_bitmap_t *destination,
+    int16_t x0, int16_t y0,
+    int16_t x1, int16_t y1,
+    uint32_t value) {
+
+    //
+    // adapted from Adafruit_CircuitPython_Display_Shapes.Polygon._line
+    //
+
+    // update the dirty rectangle
+    int16_t xbb0, xbb1, ybb0, ybb1;
+    if (x0 < x1) {
+        xbb0 = x0;
+        xbb1 = x1 + 1;
+    } else {
+        xbb0 = x1;
+        xbb1 = x0 + 1;
+    }
+    if (y0 < y1) {
+        ybb0 = y0;
+        ybb1 = y1 + 1;
+    } else {
+        ybb0 = y1;
+        ybb1 = y0 + 1;
+    }
+    displayio_area_t area = { xbb0, ybb0, xbb1, ybb1, NULL };
+    displayio_area_t bitmap_area = { 0, 0, destination->width, destination->height, NULL };
+    displayio_area_compute_overlap(&area, &bitmap_area, &area);
+
+    displayio_bitmap_set_dirty_area(destination, &area);
+
+    draw_line(destination, x0, y0, x1, y1, value);
+}
+
+STATIC int32_t ith(void *data, size_t i, int element_size) {
+    switch (element_size) {
+        default:
+        case 1:
+            return *((int8_t *)data + i);
+        case 2:
+            return *((int16_t *)data + i);
+        case 4:
+            return *((int32_t *)data + i);
+    }
+}
+
+void common_hal_bitmaptools_draw_polygon(displayio_bitmap_t *destination, void *xs, void *ys, size_t points_len, int point_size, uint32_t value, bool close) {
+    int16_t x0, y0, xmin, xmax, ymin, ymax, xprev, yprev, x, y;
+    x0 = ith(xs, 0, point_size);
+    xmin = x0;
+    xmax = x0;
+    xprev = x0;
+    y0 = ith(ys, 0, point_size);
+    ymin = y0;
+    ymax = y0;
+    yprev = y0;
+
+    for (size_t i = 1; i < points_len; i++) {
+        x = ith(xs, i, point_size);
+        y = ith(ys, i, point_size);
+        draw_line(destination, xprev, yprev, x, y, value);
+        xprev = x;
+        yprev = y;
+        xmin = MIN(xmin, x);
+        xmax = MAX(xmax, x);
+        ymin = MIN(ymin, y);
+        ymax = MAX(ymax, y);
+    }
+    if (close) {
+        draw_line(destination, xprev, yprev, x0, y0, value);
+    }
+
+    displayio_area_t area = { xmin, ymin, xmax, ymax, NULL };
+    displayio_area_t bitmap_area = { 0, 0, destination->width, destination->height, NULL };
+    displayio_area_compute_overlap(&area, &bitmap_area, &area);
+    displayio_bitmap_set_dirty_area(destination, &area);
+}
+
 void common_hal_bitmaptools_arrayblit(displayio_bitmap_t *self, void *data, int element_size, int x1, int y1, int x2, int y2, bool skip_specified, uint32_t skip_value) {
     uint32_t mask = (1 << common_hal_displayio_bitmap_get_bits_per_value(self)) - 1;