From 08084e5a97b3455e3629d0b9d803d7bb7ee13800 Mon Sep 17 00:00:00 2001
From: AllyTally <alexiatilde@gmail.com>
Date: Thu, 9 Mar 2023 14:58:58 -0400
Subject: [PATCH] Add edge-guides for horizontal gravity lines

These visualize the horizontal gravity line kludge for rooms beside
eachother. When you enter another room, gravity lines which look like
they're connected between the rooms try to have the same activated
state.

Basically, if you're in room (1,4) and you go into (2,4), if a
gravity line in (1,4) is activated (gray, on cooldown) and it's
touching the gravity line in (2,4), that gravity line will also be
activated.
---
 desktop_version/src/Editor.cpp | 36 ++++++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/desktop_version/src/Editor.cpp b/desktop_version/src/Editor.cpp
index d66f2f81..6591bd70 100644
--- a/desktop_version/src/Editor.cpp
+++ b/desktop_version/src/Editor.cpp
@@ -467,6 +467,42 @@ static void draw_edgeguides(void)
         // Bottom edge
         draw_edgeguide(ed.get_abs_tile_type(global_x + i, global_y + 30, true), i * 8, 238, true);
     }
+
+    static const SDL_Color green = graphics.getRGB(127, 255 - help.glow, 127);
+
+    // Horizontal gravity line edge-guides
+
+    for (size_t i = 0; i < customentities.size(); ++i)
+    {
+        const CustomEntity* entity = &customentities[i];
+        const bool is_horizontal_gravity_line = entity->t == 11 && entity->p1 == 0;
+        if (!is_horizontal_gravity_line)
+        {
+            continue;
+        }
+        const int x = entity->p2 * 8;
+        const int w = entity->p3;
+        const int room_x = (entity->x / 40);
+        const int room_y = (entity->y / 30);
+        if (room_y != ed.levy)
+        {
+            continue;
+        }
+        if (room_x == POS_MOD(ed.levx - 1, cl.mapwidth)
+            // It's to the left...
+            && x + w >= 312)
+        {
+            // And touching the right edge!
+            graphics.fill_rect(x, (entity->y % 30) * 8, 2, 8, green);
+        }
+        else if (room_x == POS_MOD(ed.levx + 1, cl.mapwidth)
+            // It's to the right...
+            && x <= 0)
+        {
+            // And touching the left edge!
+            graphics.fill_rect(x + w - 2, (entity->y % 30) * 8, 2, 8, green);
+        }
+    }
 }
 
 static void update_entities(void)