From 8a93587eaa61d124298ab5d9c1cdf5fcd3a64f30 Mon Sep 17 00:00:00 2001
From: Thomas Prowse <152029833+SardineMilk@users.noreply.github.com>
Date: Thu, 12 Mar 2026 10:36:53 +0000
Subject: [PATCH] Fix raycasting logic in models_basic_voxel.c (#5643)

The original logic iterated through the world and broke at the first found voxel that intersected the ray. This broke in some cases, removing a voxel out of view. I changed the algorithm to track the closest found voxel, and remove it at the end of the loop if one was found.
---
 examples/models/models_basic_voxel.c | 26 +++++++++++++++++++-------
 1 file changed, 19 insertions(+), 7 deletions(-)

diff --git a/examples/models/models_basic_voxel.c b/examples/models/models_basic_voxel.c
index b0f4bc65e..2e2756f2b 100644
--- a/examples/models/models_basic_voxel.c
+++ b/examples/models/models_basic_voxel.c
@@ -72,6 +72,7 @@ int main(void)
         UpdateCamera(&camera, CAMERA_FIRST_PERSON);
 
         // Handle voxel removal with mouse click
+        // This method is quite inefficient. Ray marching through the voxel grid using DDA would be faster, but more complex.
         if (IsMouseButtonPressed(MOUSE_LEFT_BUTTON))
         {
             // Cast a ray from the screen center (where crosshair would be)
@@ -79,12 +80,14 @@ int main(void)
             Ray ray = GetMouseRay(screenCenter, camera);
 
             // Check ray collision with all voxels
-            bool voxelRemoved = false;
-            for (int x = 0; (x < WORLD_SIZE) && !voxelRemoved; x++)
+            float closestDistance = 99999.0f;
+            Vector3 closestVoxelPosition = { -1, -1, -1 };
+            bool voxelFound = false;
+            for (int x = 0; x < WORLD_SIZE; x++)
             {
-                for (int y = 0; (y < WORLD_SIZE) && !voxelRemoved; y++)
+                for (int y = 0; y < WORLD_SIZE; y++)
                 {
-                    for (int z = 0; (z < WORLD_SIZE) && !voxelRemoved; z++)
+                    for (int z = 0; z < WORLD_SIZE; z++)
                     {
                         if (!voxels[x][y][z]) continue; // Skip empty voxels
 
@@ -97,14 +100,23 @@ int main(void)
 
                         // Check ray-box collision
                         RayCollision collision = GetRayCollisionBox(ray, box);
-                        if (collision.hit)
+                        if (collision.hit && (collision.distance < closestDistance))
                         {
-                            voxels[x][y][z] = false;    // Remove this voxel
-                            voxelRemoved = true;        // Exit all loops
+                            closestDistance = collision.distance;
+                            closestVoxelPosition = (Vector3){ x, y, z };
+                            voxelFound = true;
                         }
                     }
                 }
             }
+            
+            // Remove the closest voxel if one was hit
+            if (voxelFound)
+            {
+                voxels[(int)closestVoxelPosition.x]
+                      [(int)closestVoxelPosition.y]
+                      [(int)closestVoxelPosition.z] = false;
+            }
         }
         //----------------------------------------------------------------------------------