ui projection almost works. but scaling is wrong

1 files changed, 13 insertions, 6 deletions

diff --git a/client/src/ui.rs b/client/src/ui.rs
index be206b5..a5ff775 100644
--- a/client/src/ui.rs
+++ b/client/src/ui.rs
@@ -20,7 +20,7 @@ use egui::{
     epaint::{ImageDelta, Primitive, Vertex},
 };
 use glam::{Affine3A, Mat2, Mat3, Mat4, Vec2, Vec3Swizzles, Vec4Swizzles, vec2, vec4};
-use log::info;
+use log::{info, warn};
 use rand::random;
 use std::{
     collections::HashMap,
@@ -338,20 +338,27 @@ impl UiRenderer {
 
             let mouse_xy_clip = (input_state.cursor_pos / screen_size) * 2. - 1.;
 
-            let iproject = projection.inverse();
+            if projection.determinant() < 0e-4 {
+                warn!("bad UI projection")
+            }
 
-            let mut mouse_world_1 = iproject * vec4(mouse_xy_clip.x, mouse_xy_clip.y, 0.0, 1.0);
-            let mut mouse_world_2 = iproject * vec4(mouse_xy_clip.x, mouse_xy_clip.y, 1.0, 1.0);
+            let unproject = projection.inverse();
 
+            let mut mouse_world_1 = unproject * vec4(mouse_xy_clip.x, -mouse_xy_clip.y, 0.0, 1.0);
+            let mut mouse_world_2 = unproject * vec4(mouse_xy_clip.x, -mouse_xy_clip.y, 1.0, 1.0);
             mouse_world_1 /= mouse_world_1.w;
             mouse_world_2 /= mouse_world_2.w;
-
             let mouse_world_1 = mouse_world_1.xyz();
             let mouse_world_2 = mouse_world_2.xyz();
 
             let ray_norm = (mouse_world_2 - mouse_world_1).normalize();
             let ray_t = mouse_world_1.z / ray_norm.z;
-            let ray_hit = mouse_world_1 + ray_norm * ray_t;
+            let ray_hit = mouse_world_1 - ray_norm * ray_t;
+
+            debug_assert!(ray_hit.z.abs() < 0.1, "mouse was not projected properly");
+
+            eprintln!("z={} t={ray_t}", mouse_world_1.z);
+            eprintln!("hit={ray_hit}");
 
             let cursor_pos = ray_hit.xy();