fix(shader): Correct WGSL loop syntax in calc_shadow

- Replaced invalid 'i++' with 'i = i + 1' in the shader's calc_shadow function loop.
- This resolves the shader parsing error and allows the 3D renderer test to run successfully on all platforms.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/3d/renderer.cc b/src/3d/renderer.cc
index 14c05f7..13917b1 100644
--- a/src/3d/renderer.cc
+++ b/src/3d/renderer.cc
@@ -122,7 +122,7 @@ fn map_scene(p: vec3<f32>) -> f32 {
 fn calc_shadow(ro: vec3<f32>, rd: vec3<f32>, tmin: f32, tmax: f32) -> f32 {
     var t = tmin;
     var res = 1.0;
-    for (var i = 0; i < 30; i++) {
+    for (var i = 0; i < 30; i = i + 1) {
         let h = map_scene(ro + rd * t);
         if (h < 0.001) {
             return 0.0; // Hard shadow hit