From f4bae5a5d5e5e11267660affd524f345cf9abdc7 Mon Sep 17 00:00:00 2001
From: Jaklyy <102590697+Jaklyy@users.noreply.github.com>
Date: Sat, 10 Feb 2024 17:39:40 -0500
Subject: [PATCH] best approximation so far

---
 src/GPU3D_Soft.h | 23 ++++++++++++-----------
 1 file changed, 12 insertions(+), 11 deletions(-)

diff --git a/src/GPU3D_Soft.h b/src/GPU3D_Soft.h
index 9cfdf9ad..51a87339 100644
--- a/src/GPU3D_Soft.h
+++ b/src/GPU3D_Soft.h
@@ -194,22 +194,23 @@ private:
                     disp = z0 - z1,
                     factor = xdiff - x;
                 }
-
+                /*
                 if (dir)
                 {
-                    int shift = 0;
-                    while (disp > 0x3FF)
+                    return base + disp * factor / xdiff;
+                }
+                else*/
+                {
+                    u32 recip, recip2;
+                    u32 shift = 0;
+                    recip2 = recip = (factor << 16) / xdiff;
+                    while (recip2 > 0x100)
                     {
-                        disp >>= 1;
+                        recip2 >>= 1;
                         shift++;
                     }
-
-                    return base + ((((s64)disp * factor * xrecip_z) >> 22) << shift);
-                }
-                else
-                {
-                    disp >>= 9;
-                    return base + (((s64)disp * factor * xrecip_z) >> 13);
+                    disp >>= shift;
+                    return base + ((disp * recip) >> (16 - shift));
                 }
             }
         }