working on cube (hardcoded)

1 files changed, 19 insertions, 0 deletions

diff --git a/src/maths/maths.h b/src/maths/maths.h
index 41fbdfc..9206c5c 100644
--- a/src/maths/maths.h
+++ b/src/maths/maths.h
@@ -132,6 +132,24 @@ static inline mat4 mat4_mult(mat4 lhs, mat4 rhs) {
   return out_matrix;
 }
 
+#if defined(CEL_REND_BACKEND_VULKAN)
+/** @brief Creates a perspective projection matrix compatible with Vulkan */
+static inline mat4 mat4_perspective(f32 fov_radians, f32 aspect_ratio, f32 near_clip, f32 far_clip) {
+    // near_clip *= -1.0;
+    // far_clip *= -1.0;
+
+    f32 half_tan_fov = tanf(fov_radians * 0.5f);
+    mat4 out_matrix = { .data = { 0 } };
+    
+    out_matrix.data[0] = 1.0f / (aspect_ratio * half_tan_fov);
+    out_matrix.data[5] = -1.0f / half_tan_fov; // Flip Y-axis for Vulkan
+    out_matrix.data[10] = -((far_clip + near_clip) / (far_clip - near_clip));
+  out_matrix.data[11] = -1.0f;
+  out_matrix.data[14] = -((2.0f * far_clip * near_clip) / (far_clip - near_clip));
+
+    return out_matrix;
+}
+#else
 /** @brief Creates a perspective projection matrix */
 static inline mat4 mat4_perspective(f32 fov_radians, f32 aspect_ratio, f32 near_clip,
                                     f32 far_clip) {
@@ -144,6 +162,7 @@ static inline mat4 mat4_perspective(f32 fov_radians, f32 aspect_ratio, f32 near_
   out_matrix.data[14] = -((2.0f * far_clip * near_clip) / (far_clip - near_clip));
   return out_matrix;
 }
+#endif
 
 /** @brief Creates an orthographic projection matrix */
 static inline mat4 mat4_orthographic(f32 left, f32 right, f32 bottom, f32 top, f32 near_clip,