From fb1d3eda51cd9d89083130cf9932c7bde758756c Mon Sep 17 00:00:00 2001
From: Aki <please@ignore.pl>
Date: Sat, 4 Feb 2023 01:04:03 +0100
Subject: Full grid is now drawn

---
 engine/include/kurator/engine/Camera.h |  3 +++
 engine/src/Camera.cpp                  | 21 ++++++++++++++++++++
 kurator/src/Grid.cpp                   | 36 +++++++++++++++++++++-------------
 3 files changed, 46 insertions(+), 14 deletions(-)

diff --git a/engine/include/kurator/engine/Camera.h b/engine/include/kurator/engine/Camera.h
index 2eb192a..d5253df 100644
--- a/engine/include/kurator/engine/Camera.h
+++ b/engine/include/kurator/engine/Camera.h
@@ -15,6 +15,9 @@ struct Camera
 	double scale = 1.0;
 	Point to_world(const Point& screen) const;
 	Point to_screen(const Point& world) const;
+	Point top_left() const;
+	Point center() const;
+	Point bottom_right() const;
 };
 
 
diff --git a/engine/src/Camera.cpp b/engine/src/Camera.cpp
index 41cc5ab..4a95ad8 100644
--- a/engine/src/Camera.cpp
+++ b/engine/src/Camera.cpp
@@ -29,6 +29,27 @@ Camera::to_screen(const Point& world) const
 
 
 Point
+Camera::top_left() const
+{
+	return to_world({0.0, 0.0});
+}
+
+
+Point
+Camera::center() const
+{
+	return to_world(viewport().scale(0.5));
+}
+
+
+Point
+Camera::bottom_right() const
+{
+	return to_world(viewport());
+}
+
+
+Point
 viewport()
 {
 	return {static_cast<double>(GetScreenWidth()), static_cast<double>(GetScreenHeight())};
diff --git a/kurator/src/Grid.cpp b/kurator/src/Grid.cpp
index 4243bc9..633b906 100644
--- a/kurator/src/Grid.cpp
+++ b/kurator/src/Grid.cpp
@@ -1,5 +1,7 @@
 #include "Grid.h"
 
+#include <cmath>
+
 #include <raylib.h>
 
 #include <kurator/engine/Camera.h>
@@ -9,23 +11,29 @@ namespace kurator
 {
 
 
+constexpr Color GRID {0x11, 0x11, 0x11, 0xff};
+constexpr Color CENTER {0x31, 0x31, 0x31, 0xff};
+
+
 void
 Grid::draw(const engine::Camera& camera) const
 {
-	const int width = GetScreenWidth();
-	const int height = GetScreenHeight();
-	DrawLine(
-		width/2 - camera.offset.x*camera.scale,
-		0,
-		width/2 - camera.offset.x*camera.scale,
-		height,
-		DARKGRAY);
-	DrawLine(
-		0,
-		height/2 - camera.offset.y*camera.scale,
-		width,
-		height/2 - camera.offset.y*camera.scale,
-		DARKGRAY);
+	constexpr double step = 1000.0;
+	auto start = camera.top_left();
+	start.x = std::round(start.x / step) * step;
+	start.y = std::round(start.y / step) * step;
+	const auto end = camera.bottom_right();
+	auto point = start;
+	while (point.x < end.x || point.y < end.y) {
+		const auto projected = camera.to_screen(point);
+		DrawLine(projected.x, 0, projected.x, GetScreenHeight(), GRID);
+		DrawLine(0, projected.y, GetScreenWidth(), projected.y, GRID);
+		point.x += step;
+		point.y += step;
+	}
+	const auto center = camera.to_screen({0.0, 0.0});
+	DrawLine(center.x, 0, center.x, GetScreenHeight(), CENTER);
+	DrawLine(0, center.y, GetScreenWidth(), center.y, CENTER);
 }
 
 
-- 
cgit v1.1