diff --git a/src/rendering/twn_draw.c b/src/rendering/twn_draw.c
index ed68e72..0705155 100644
--- a/src/rendering/twn_draw.c
+++ b/src/rendering/twn_draw.c
@@ -521,19 +521,31 @@ DrawCameraUnprojectResult draw_camera_unproject(Vec2 point,
         .far_z = draw_distance
     };
 
-    Matrix4 const projection_matrix = orthographic ? camera_orthographic(&camera) : camera_perspective(&camera);
-    Matrix4 const look_at_matrix    = camera_look_at(&camera);
-    /* TODO: cache matrices for repeated camera inputs, those are expensive */
-    Matrix4 const inverse_view_proj = matrix_inverse(matrix_multiply(projection_matrix, look_at_matrix));
-
     point.y = (float)ctx.base_render_height - point.y;
 
     Vec4 v;
     v.x = 2.0f * point.x / (float)ctx.base_render_width  - 1.0f;
     v.y = 2.0f * point.y / (float)ctx.base_render_height - 1.0f;
-    v.z = 2.0f * 1.0f                                    - 1.0f;
+    v.z = 2.0f * 1.0f - 1.0f;
     v.w = 1.0f;
 
+    /* simpler case, just shoot a point from viewbox face along the supplied direction */
+    if (orthographic) {
+        Vec3 right = vec3_cross(direction, up);
+        Vec3 aup = vec3_cross(direction, right);
+        return (DrawCameraUnprojectResult){
+            .direction = direction,
+            .position = vec3_add(vec3_add(position, vec3_scale(right, v.x * aspect/zoom)), vec3_scale(aup, -v.y * aspect/zoom)),
+        };
+    }
+
+    /* TODO: sanity check for point being in proper box? it would produce bogus results otherwise */
+
+    Matrix4 const projection_matrix = orthographic ? camera_orthographic(&camera) : camera_perspective(&camera);
+    Matrix4 const look_at_matrix    = camera_look_at(&camera);
+    /* TODO: cache matrices for repeated camera inputs, those are expensive */
+    Matrix4 const inverse_view_proj = matrix_inverse(matrix_multiply(projection_matrix, look_at_matrix));
+
     v = matrix_vector_multiply(inverse_view_proj, v);
 
     /* TODO: is it even ever not equal to 1 in our case ? */