implement renderer

1 files changed, 62 insertions, 0 deletions

diff --git a/lib/nes/app/graphics/renderer.hh b/lib/nes/app/graphics/renderer.hh
new file mode 100644
index 0000000..7b46461
--- /dev/null
+++ b/lib/nes/app/graphics/renderer.hh
@@ -0,0 +1,62 @@
+#pragma once
+
+#include <string_view>
+#include <cstdint>
+
+namespace nes
+{
+	class display;
+	class rgb;
+} // namespace nes
+
+namespace nes::app
+{
+	struct image_tile;
+	struct mask_tile;
+	class image_view;
+	enum class color : std::uint8_t;
+
+	/// Renders tiles and other primitive shapes onto a display.
+	///
+	/// The renderer sees the display as a canvas divided into 8x8 tiles. All elements (except shadows and borders) must
+	/// be arranged  on this 8x8 grid.
+	class renderer
+	{
+		display& display_;
+
+	public:
+		static constexpr auto width = unsigned{ 32 };
+		static constexpr auto height = unsigned{ 30 };
+
+		explicit renderer(display&);
+
+		renderer(renderer const&) = delete;
+		renderer(renderer&&) = delete;
+		auto operator=(renderer const&) -> renderer& = delete;
+		auto operator=(renderer&&) -> renderer& = delete;
+
+		/// If set, add a drop shadow behind newly drawn opaque elements.
+		auto set_shadow(unsigned x_px, unsigned y_px, color) -> void;
+		/// If set, add an inner border inside newly drawn opaque elements.
+		auto set_border(unsigned px, color) -> void;
+
+		/// Render a colored tile at the given tile coordinates.
+		auto render_image_tile(unsigned x, unsigned y, image_tile) -> void;
+		/// Render an alpha-only tile at the given tile coordinates with the given color.
+		auto render_mask_tile(unsigned x, unsigned y, mask_tile, color) -> void;
+		/// Render an image at the given tile coordinates.
+		auto render_image(unsigned x, unsigned y, image_view) -> void;
+		/// Render a string of text at the given tile coordinates (one tile per character).
+		auto render_text(unsigned x, unsigned y, std::string_view, color) -> void;
+		/// Render a string of text at the given tile coordinates, limiting its length to the given width and
+		/// ellipsizing afterward.
+		auto render_text(unsigned x, unsigned y, std::string_view, unsigned width, color) -> void;
+		/// Render a rectangle at the given tile coordinates with a given size (measured in tiles).
+		auto render_rect(unsigned x, unsigned y, unsigned width, unsigned height, color) -> void;
+		/// Completely fill the screen.
+		auto render_fill(color) -> void;
+
+	private:
+		auto resolve_color(color) const -> rgb;
+	};
+} // namespace nes::app
\ No newline at end of file