From e0e1b978603d8504f8b1b68d53f32a8c325da00b Mon Sep 17 00:00:00 2001
From: lisyarus <lisyarus@gmail.com>
Date: Sat, 27 Feb 2021 16:38:58 +0300
Subject: [PATCH] Add ui::image_view element

---
 libs/ui/include/psemek/ui/image_view.hpp | 45 ++++++++++++
 libs/ui/source/image_view.cpp            | 87 ++++++++++++++++++++++++
 2 files changed, 132 insertions(+)
 create mode 100644 libs/ui/include/psemek/ui/image_view.hpp
 create mode 100644 libs/ui/source/image_view.cpp

diff --git a/libs/ui/include/psemek/ui/image_view.hpp b/libs/ui/include/psemek/ui/image_view.hpp
new file mode 100644
index 00000000..cfc860a1
--- /dev/null
+++ b/libs/ui/include/psemek/ui/image_view.hpp
@@ -0,0 +1,45 @@
+#pragma once
+
+#include <psemek/ui/element.hpp>
+#include <psemek/ui/box_shape.hpp>
+
+#include <psemek/gfx/texture.hpp>
+
+namespace psemek::ui
+{
+
+	struct image_view
+		: element
+	{
+		virtual bool upscale() const { return upscale_; }
+		virtual void set_upscale(bool value);
+
+		virtual bool downscale() const { return downscale_; }
+		virtual void set_downscale(bool value);
+
+		virtual bool keep_aspect_ratio() const { return keep_aspect_ratio_; }
+		virtual void set_keep_aspect_ratio(bool value);
+
+		virtual std::shared_ptr<gfx::texture_2d> image() const { return image_; }
+		virtual void set_image(std::shared_ptr<gfx::texture_2d> image);
+
+		virtual gfx::color_rgba const & color() const { return color_; }
+		virtual void set_color(gfx::color_rgba const & c) { color_ = c; }
+
+		struct shape const & shape() const override { return shape_; }
+		void reshape(geom::box<float, 2> const & bbox) override { shape_.box = bbox; }
+
+		geom::box<float, 2> size_constraints() const override;
+
+		void draw(painter & p) const override;
+
+	private:
+		bool upscale_ = true;
+		bool downscale_ = true;
+		bool keep_aspect_ratio_ = true;
+		std::shared_ptr<gfx::texture_2d> image_;
+		gfx::color_rgba color_{0, 0, 0, 0};
+		box_shape shape_;
+	};
+
+}
diff --git a/libs/ui/source/image_view.cpp b/libs/ui/source/image_view.cpp
new file mode 100644
index 00000000..0e5b8269
--- /dev/null
+++ b/libs/ui/source/image_view.cpp
@@ -0,0 +1,87 @@
+#include <psemek/ui/image_view.hpp>
+
+namespace psemek::ui
+{
+
+	void image_view::set_upscale(bool value)
+	{
+		upscale_ = value;
+		post_reshape();
+	}
+
+	void image_view::set_downscale(bool value)
+	{
+		downscale_ = value;
+		post_reshape();
+	}
+
+	void image_view::set_keep_aspect_ratio(bool value)
+	{
+		keep_aspect_ratio_ = value;
+		post_reshape();
+	}
+
+	void image_view::set_image(std::shared_ptr<gfx::texture_2d> image)
+	{
+		image_ = std::move(image);
+		post_reshape();
+	}
+
+	geom::box<float, 2> image_view::size_constraints() const
+	{
+		auto r = element::size_constraints();
+
+		if (image_)
+		{
+			auto const size = image_->size();
+
+			if (!downscale_)
+			{
+				r[0].min = size[0];
+				r[1].min = size[1];
+			}
+
+			if (!upscale_)
+			{
+				r[0].max = size[0];
+				r[1].max = size[1];
+			}
+		}
+
+		return r;
+	}
+
+	void image_view::draw(painter & p) const
+	{
+		if (!image_) return;
+
+		auto const size = image_->size();
+
+		auto box = shape_.box;
+
+		if (!upscale_)
+		{
+			if (size[0] < box[0].length())
+				box[0] = geom::shrink(box[0], (box[0].length() - size[0]) / 2.f);
+			if (size[1] < box[1].length())
+				box[1] = geom::shrink(box[1], (box[1].length() - size[1]) / 2.f);
+		}
+
+		if (keep_aspect_ratio_ && size[0] > 0.f && size[1] > 0.f)
+		{
+			if (size[0] * box[1].length() < box[0].length() * size[1])
+			{
+				float const width = box[1].length() * size[0] / size[1];
+				box[0] = geom::shrink(box[0], (box[0].length() - width) / 2.f);
+			}
+			else
+			{
+				float const height = box[0].length() * size[1] / size[0];
+				box[1] = geom::shrink(box[1], (box[1].length() - height) / 2.f);
+			}
+		}
+
+		p.draw_image(box, *image_, color_);
+	}
+
+}