[studio/modlib] Add SelectionTracker

src/olympic/studio/modlib/include/studio/selectiontracker.hpp

@@ -0,0 +1,90 @@
+
+#pragma once
+
+#include <imgui.h>
+
+#include <ox/std/math.hpp>
+#include <ox/std/point.hpp>
+#include <ox/std/typetraits.hpp>
+
+namespace studio {
+
+struct Selection {ox::Point a, b;};
+
+constexpr auto iterateSelection(studio::Selection const&sel, auto const&cb) {
+	for (auto x = sel.a.x; x <= sel.b.x; ++x) {
+		for (auto y = sel.a.y; y <= sel.b.y; ++y) {
+			if constexpr(ox::is_same_v<decltype(cb(x, y)), ox::Error>) {
+				return cb(x, y);
+			} else {
+				cb(x, y);
+			}
+		}
+	}
+};
+
+class SelectionTracker {
+	private:
+		bool m_selectionOngoing{};
+		ox::Point m_pointA;
+		ox::Point m_pointB;
+	public:
+		[[nodiscard]]
+		constexpr bool selectionOngoing() const noexcept {
+			return m_selectionOngoing;
+		}
+
+		constexpr void startSelection(ox::Point cursor) noexcept {
+			m_pointA = cursor;
+			m_pointB = cursor;
+			m_selectionOngoing = true;
+		}
+
+		constexpr void updateCursorPoint(ox::Point cursor, bool allowStart = true) noexcept {
+			if (!m_selectionOngoing && allowStart) {
+				m_pointA = cursor;
+				m_selectionOngoing = true;
+			}
+			if (m_selectionOngoing) {
+				m_pointB = cursor;
+			}
+		}
+
+		constexpr void updateCursorPoint(ox::Vec2 cursor, bool allowStart = true) noexcept {
+			updateCursorPoint(
+					ox::Point{
+							static_cast<int32_t>(cursor.x),
+							static_cast<int32_t>(cursor.y),
+					},
+					allowStart);
+		}
+
+		constexpr void updateCursorPoint(ImVec2 cursor, bool allowStart = true) noexcept {
+			updateCursorPoint(
+					ox::Point{
+						static_cast<int32_t>(cursor.x),
+						static_cast<int32_t>(cursor.y),
+					},
+					allowStart);
+		}
+
+		constexpr void finishSelection() noexcept {
+			m_selectionOngoing = {};
+		}
+
+		[[nodiscard]]
+		constexpr Selection selection() const noexcept {
+			return {
+				{
+					ox::min(m_pointA.x, m_pointB.x),
+					ox::min(m_pointA.y, m_pointB.y),
+				},
+				{
+					ox::max(m_pointA.x, m_pointB.x),
+					ox::max(m_pointA.y, m_pointB.y),
+				},
+			};
+		}
+};
+
+}

src/olympic/studio/modlib/include/studio/studio.hpp

@@ -4,7 +4,6 @@
 
 #pragma once
 
-#include <studio/color.hpp>
 #include <studio/context.hpp>
 #include <studio/editor.hpp>
 #include <studio/filedialog.hpp>
@@ -13,6 +12,7 @@
 #include <studio/itemmaker.hpp>
 #include <studio/popup.hpp>
 #include <studio/project.hpp>
+#include <studio/selectiontracker.hpp>
 #include <studio/task.hpp>
 #include <studio/undocommand.hpp>
 #include <studio/undostack.hpp>