Standalone app api v3 (#2772)

Added file io, and updated some ui elements.
Also added Digital Rain standalone app for an example.

firmware/standalone/digitalrain/ui/ui_painter.hpp

@@ -0,0 +1,113 @@
+/*
+ * Copyright (C) 2014 Jared Boone, ShareBrained Technology, Inc.
+ *
+ * This file is part of PortaPack.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#ifndef __UI_PAINTER_H__
+#define __UI_PAINTER_H__
+
+#include "ui.hpp"
+#include "ui_text.hpp"
+
+#include <string_view>
+#include <array>
+#include <vector>
+
+namespace ui {
+
+struct Style {
+    const Font& font;
+    const Color background;
+    const Color foreground;
+
+    Style invert() const;
+};
+
+/* Sometimes mutation is just the more readable thing... */
+struct MutableStyle {
+    const Font* font;
+    Color background;
+    Color foreground;
+
+    MutableStyle(const Style& s)
+        : font{&s.font},
+          background{s.background},
+          foreground{s.foreground} {}
+
+    void invert() {
+        std::swap(background, foreground);
+    }
+
+    operator Style() const {
+        return {
+            .font = *font,
+            .background = background,
+            .foreground = foreground};
+    }
+};
+
+class Widget;
+
+class Painter {
+   public:
+    Painter() {};
+
+    Painter(const Painter&) = delete;
+    Painter(Painter&&) = delete;
+
+    int draw_char(Point p, const Style& style, char c);
+
+    int draw_string(Point p, const Style& style, std::string_view text);
+    int draw_string(Point p, const Font& font, Color foreground, Color background, std::string_view text);
+
+    void draw_bitmap(Point p, const Bitmap& bitmap, Color background, Color foreground);
+
+    void draw_rectangle(Rect r, Color c);
+    void fill_rectangle(Rect r, Color c);
+    void fill_rectangle_unrolled8(Rect r, Color c);
+
+    void paint_widget_tree(Widget* w);
+
+    void draw_hline(Point p, int width, Color c);
+    void draw_vline(Point p, int height, Color c);
+
+    template <size_t N>
+    void draw_pixels(
+        const ui::Rect r,
+        const std::array<ui::Color, N>& colors) {
+        draw_pixels(r, colors.data(), colors.size());
+    }
+
+    void draw_pixels(
+        const ui::Rect r,
+        const std::vector<ui::Color>& colors) {
+        draw_pixels(r, colors.data(), colors.size());
+    }
+
+    void draw_pixels(const ui::Rect r, const ui::Color* const colors, const size_t count);
+    void draw_line(const ui::Point start, const ui::Point end, const ui::Color color);
+    void draw_pixel(const ui::Point p, const ui::Color color);
+
+   private:
+    void paint_widget(Widget* w);
+};
+
+} /* namespace ui */
+
+#endif /*__UI_PAINTER_H__*/