A variety of displayio improvements

This changes a number of things in displayio:
* Introduces BuiltinFont and Glyph so the built in font can be used by libraries. For boards with
  a font it is available as board.TERMINAL_FONT. Fixes #1172
* Remove _load_row from Bitmap in favor of bitmap[] access. Index can be x/y tuple or overall index. Fixes #1191
* Add width and height properties to Bitmap.
* Add insert and [] access to Group. Fixes #1518
* Add index param to pop on Group.
* Terminal no longer takes unicode character info. It takes a BuiltinFont instead.
* Fix Terminal's handling of [###D vt100 commands used when up arrowing into repl history.
* Add x and y positions to Group plus scale as well.
* Add bitmap accessor for BuiltinFont

7 files changed, 224 insertions, 18 deletions

diff --git a/shared-module/displayio/Bitmap.c b/shared-module/displayio/Bitmap.c
index addc341a7..2b2c70ab6 100644
--- a/shared-module/displayio/Bitmap.c
+++ b/shared-module/displayio/Bitmap.c
@@ -42,7 +42,7 @@ void common_hal_displayio_bitmap_construct(displayio_bitmap_t *self, uint32_t wi
     self->width = width;
     self->height = height;
     self->data = m_malloc(self->stride * height * sizeof(uint32_t), false);
-
+    self->read_only = false;
     self->bits_per_value = bits_per_value;
 
     if (bits_per_value > 8) {
@@ -64,6 +64,18 @@ void common_hal_displayio_bitmap_construct(displayio_bitmap_t *self, uint32_t wi
     self->bitmask = (1 << bits_per_value) - 1;
 }
 
+uint16_t common_hal_displayio_bitmap_get_height(displayio_bitmap_t *self) {
+    return self->height;
+}
+
+uint16_t common_hal_displayio_bitmap_get_width(displayio_bitmap_t *self) {
+    return self->width;
+}
+
+uint32_t common_hal_displayio_bitmap_get_bits_per_value(displayio_bitmap_t *self) {
+    return self->bits_per_value;
+}
+
 void common_hal_displayio_bitmap_load_row(displayio_bitmap_t *self, uint16_t y, uint8_t* data, uint16_t len) {
     if (len != self->stride * sizeof(uint32_t)) {
         mp_raise_ValueError(translate("row must be packed and word aligned"));
@@ -85,6 +97,7 @@ void common_hal_displayio_bitmap_load_row(displayio_bitmap_t *self, uint16_t y,
         row_value++;
     }
 }
+
 uint32_t common_hal_displayio_bitmap_get_pixel(displayio_bitmap_t *self, int16_t x, int16_t y) {
     if (x >= self->width || x < 0 || y >= self->height || y < 0) {
         return 0;
@@ -99,3 +112,21 @@ uint32_t common_hal_displayio_bitmap_get_pixel(displayio_bitmap_t *self, int16_t
         return self->data[row_start + x * bytes_per_value];
     }
 }
+
+void common_hal_displayio_bitmap_set_pixel(displayio_bitmap_t *self, int16_t x, int16_t y, uint32_t value) {
+    if (self->read_only) {
+        mp_raise_RuntimeError(translate("Read-only object"));
+    }
+    int32_t row_start = y * self->stride;
+    if (self->bits_per_value < 8) {
+        uint32_t bit_position = (32 - ((x & self->x_mask) + 1) * self->bits_per_value);
+        uint32_t index = row_start + (x >> self->x_shift);
+        uint32_t word = self->data[index];
+        word &= ~(self->bitmask << bit_position);
+        word |= (value & self->bitmask) << bit_position;
+        self->data[index] = word;
+    } else {
+        uint32_t bytes_per_value = self->bits_per_value / 8;
+        self->data[row_start + x * bytes_per_value] = value;
+    }
+}
diff --git a/shared-module/displayio/Bitmap.h b/shared-module/displayio/Bitmap.h
index 781a4d12a..485b57daf 100644
--- a/shared-module/displayio/Bitmap.h
+++ b/shared-module/displayio/Bitmap.h
@@ -42,6 +42,7 @@ typedef struct {
     uint8_t x_shift;
     uint8_t x_mask;
     uint16_t bitmask;
+    bool read_only;
 } displayio_bitmap_t;
 
 #endif // MICROPY_INCLUDED_SHARED_MODULE_DISPLAYIO_BITMAP_H
diff --git a/shared-module/displayio/BuiltinFont.c b/shared-module/displayio/BuiltinFont.c
new file mode 100644
index 000000000..ee69b423c
--- /dev/null
+++ b/shared-module/displayio/BuiltinFont.c
@@ -0,0 +1,79 @@
+/*
+ * This file is part of the Micro Python project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2018 Scott Shawcroft for Adafruit Industries
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "shared-bindings/displayio/BuiltinFont.h"
+
+
+#include "shared-bindings/displayio/Glyph.h"
+
+#include "py/objnamedtuple.h"
+
+mp_obj_t common_hal_displayio_builtinfont_get_bitmap(const displayio_builtinfont_t *self) {
+    return MP_OBJ_FROM_PTR(self->bitmap);
+}
+
+mp_obj_t common_hal_displayio_builtinfont_get_bounding_box(const displayio_builtinfont_t *self) {
+    mp_obj_t *items = m_new(mp_obj_t, 2);
+    items[0] = MP_OBJ_NEW_SMALL_INT(self->width);
+    items[1] = MP_OBJ_NEW_SMALL_INT(self->height);
+    return mp_obj_new_tuple(2, items);
+}
+
+uint8_t displayio_builtinfont_get_glyph_index(const displayio_builtinfont_t *self, mp_uint_t codepoint) {
+    if (codepoint >= 0x20 && codepoint <= 0x7e) {
+        return codepoint - 0x20;
+    }
+    // Do a linear search of the mapping for unicode.
+    const byte* j = self->unicode_characters;
+    uint8_t k = 0;
+    while (j < self->unicode_characters + self->unicode_characters_len) {
+        unichar potential_c = utf8_get_char(j);
+        j = utf8_next_char(j);
+        if (codepoint == potential_c) {
+            return 0x7f - 0x20 + k;
+        }
+        k++;
+    }
+    return 0xff;
+}
+
+mp_obj_t common_hal_displayio_builtinfont_get_glyph(const displayio_builtinfont_t *self, mp_uint_t codepoint) {
+    uint8_t glyph_index = displayio_builtinfont_get_glyph_index(self, codepoint);
+    if (glyph_index == 0xff) {
+        return mp_const_none;
+    }
+    mp_obj_t field_values[8] = {
+        MP_OBJ_FROM_PTR(self->bitmap),
+        MP_OBJ_NEW_SMALL_INT(glyph_index),
+        MP_OBJ_NEW_SMALL_INT(self->width),
+        MP_OBJ_NEW_SMALL_INT(self->height),
+        MP_OBJ_NEW_SMALL_INT(0),
+        MP_OBJ_NEW_SMALL_INT(0),
+        MP_OBJ_NEW_SMALL_INT(self->width),
+        MP_OBJ_NEW_SMALL_INT(0)
+    };
+    return namedtuple_make_new((const mp_obj_type_t*) &displayio_glyph_type, 8, field_values, NULL);
+}
diff --git a/shared-module/displayio/BuiltinFont.h b/shared-module/displayio/BuiltinFont.h
new file mode 100644
index 000000000..ac69ef9da
--- /dev/null
+++ b/shared-module/displayio/BuiltinFont.h
@@ -0,0 +1,47 @@
+/*
+ * This file is part of the Micro Python project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2018 Scott Shawcroft for Adafruit Industries
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef MICROPY_INCLUDED_SHARED_MODULE_DISPLAYIO_BUILTINFONT_H
+#define MICROPY_INCLUDED_SHARED_MODULE_DISPLAYIO_BUILTINFONT_H
+
+#include <stdbool.h>
+#include <stdint.h>
+
+#include "py/obj.h"
+#include "shared-bindings/displayio/Bitmap.h"
+
+typedef struct {
+    mp_obj_base_t base;
+    const displayio_bitmap_t* bitmap;
+    uint8_t width;
+    uint8_t height;
+    const byte* unicode_characters;
+    uint16_t unicode_characters_len;
+} displayio_builtinfont_t;
+
+uint8_t displayio_builtinfont_get_glyph_index(const displayio_builtinfont_t *self, mp_uint_t codepoint);
+
+#endif // MICROPY_INCLUDED_SHARED_MODULE_DISPLAYIO_BUILTINFONT_H
diff --git a/shared-module/displayio/Group.c b/shared-module/displayio/Group.c
index 95043e4f3..e40b5a7ea 100644
--- a/shared-module/displayio/Group.c
+++ b/shared-module/displayio/Group.c
@@ -29,12 +29,39 @@
 #include "py/runtime.h"
 #include "shared-bindings/displayio/TileGrid.h"
 
-void common_hal_displayio_group_construct(displayio_group_t* self, uint32_t max_size) {
+void common_hal_displayio_group_construct(displayio_group_t* self, uint32_t max_size, uint32_t scale) {
     mp_obj_t* children = m_new(mp_obj_t, max_size);
-    displayio_group_construct(self, children, max_size);
+    displayio_group_construct(self, children, max_size, scale);
 }
 
-void common_hal_displayio_group_append(displayio_group_t* self, mp_obj_t layer) {
+uint32_t common_hal_displayio_group_get_scale(displayio_group_t* self) {
+    return self->scale;
+}
+
+void common_hal_displayio_group_set_scale(displayio_group_t* self, uint32_t scale) {
+    self->scale = scale;
+    self->needs_refresh = true;
+}
+
+mp_int_t common_hal_displayio_group_get_x(displayio_group_t* self) {
+    return self->x;
+}
+
+void common_hal_displayio_group_set_x(displayio_group_t* self, mp_int_t x) {
+    self->x = x;
+    self->needs_refresh = true;
+}
+
+mp_int_t common_hal_displayio_group_get_y(displayio_group_t* self) {
+    return self->y;
+}
+
+void common_hal_displayio_group_set_y(displayio_group_t* self, mp_int_t y) {
+    self->y = y;
+    self->needs_refresh = true;
+}
+
+void common_hal_displayio_group_insert(displayio_group_t* self, size_t index, mp_obj_t layer) {
     if (self->size == self->max_size) {
         mp_raise_RuntimeError(translate("Group full"));
     }
@@ -45,29 +72,47 @@ void common_hal_displayio_group_append(displayio_group_t* self, mp_obj_t layer)
     if (native_layer == MP_OBJ_NULL) {
         mp_raise_ValueError(translate("Layer must be a Group or TileGrid subclass."));
     }
-    self->children[self->size] = layer;
+    // Shift everything right.
+    for (size_t i = index; i < self->size; i++) {
+        self->children[i + 1] = self->children[i];
+    }
+    self->children[index] = native_layer;
     self->size++;
     self->needs_refresh = true;
 }
 
-mp_obj_t common_hal_displayio_group_pop(displayio_group_t* self) {
-    if (self->size == 0) {
-        mp_raise_IndexError(translate("Group empty"));
-    }
+mp_obj_t common_hal_displayio_group_pop(displayio_group_t* self, size_t index) {
     self->size--;
-    mp_obj_t item = self->children[self->size];
+    mp_obj_t item = self->children[index];
+    // Shift everything left.
+    for (size_t i = index; i < self->size; i++) {
+        self->children[i] = self->children[i + 1];
+    }
     self->children[self->size] = NULL;
     self->needs_refresh = true;
     return item;
 }
 
-void displayio_group_construct(displayio_group_t* self, mp_obj_t* child_array, uint32_t max_size) {
+size_t common_hal_displayio_group_get_len(displayio_group_t* self) {
+    return self->size;
+}
+
+mp_obj_t common_hal_displayio_group_get(displayio_group_t* self, size_t index) {
+    return self->children[index];
+}
+
+void common_hal_displayio_group_set(displayio_group_t* self, size_t index, mp_obj_t layer) {
+    self->children[index] = layer;
+    self->needs_refresh = true;
+}
+
+void displayio_group_construct(displayio_group_t* self, mp_obj_t* child_array, uint32_t max_size, uint32_t scale) {
     self->x = 0;
     self->y = 0;
     self->children = child_array;
     self->max_size = max_size;
     self->needs_refresh = false;
-    self->scale = 1;
+    self->scale = scale;
 }
 
 bool displayio_group_get_pixel(displayio_group_t *self, int16_t x, int16_t y, uint16_t* pixel) {
@@ -86,7 +131,6 @@ bool displayio_group_get_pixel(displayio_group_t *self, int16_t x, int16_t y, ui
                 return true;
             }
         }
-        // TODO: Tiled layer
     }
     return false;
 }
diff --git a/shared-module/displayio/Group.h b/shared-module/displayio/Group.h
index 60f573ff6..265cb4e22 100644
--- a/shared-module/displayio/Group.h
+++ b/shared-module/displayio/Group.h
@@ -43,11 +43,7 @@ typedef struct {
     bool needs_refresh;
 } displayio_group_t;
 
-
-void common_hal_displayio_group_construct(displayio_group_t* self, uint32_t max_size);
-void common_hal_displayio_group_append(displayio_group_t* self, mp_obj_t layer);
-
-void displayio_group_construct(displayio_group_t* self, mp_obj_t* child_array, uint32_t max_size);
+void displayio_group_construct(displayio_group_t* self, mp_obj_t* child_array, uint32_t max_size, uint32_t scale);
 bool displayio_group_get_pixel(displayio_group_t *group, int16_t x, int16_t y, uint16_t *pixel);
 bool displayio_group_needs_refresh(displayio_group_t *self);
 void displayio_group_finish_refresh(displayio_group_t *self);
diff --git a/shared-module/displayio/TileGrid.c b/shared-module/displayio/TileGrid.c
index b90603afe..e4f40a5f7 100644
--- a/shared-module/displayio/TileGrid.c
+++ b/shared-module/displayio/TileGrid.c
@@ -40,9 +40,17 @@ void common_hal_displayio_tilegrid_construct(displayio_tilegrid_t *self, mp_obj_
     // Sprites will only have one tile so save a little memory by inlining values in the pointer.
     uint8_t inline_tiles = sizeof(uint8_t*);
     if (total_tiles <= inline_tiles) {
+        self->tiles = 0;
+        // Pack values into the pointer since there are only a few.
+        for (uint32_t i = 0; i < inline_tiles; i++) {
+            ((uint8_t*) &self->tiles)[i] = default_tile;
+        }
         self->inline_tiles = true;
     } else {
         self->tiles = (uint8_t*) m_malloc(total_tiles, false);
+        for (uint32_t i = 0; i < total_tiles; i++) {
+            self->tiles[i] = default_tile;
+        }
         self->inline_tiles = false;
     }
     self->bitmap_width_in_tiles = bitmap_width_in_tiles;