From 950cc3ce167ef9825011a9a2d8e867ddfc28d8fe Mon Sep 17 00:00:00 2001
From: Dane Johnson <dane_johnson@ymail.com>
Date: Fri, 22 Jan 2021 14:37:32 -0600
Subject: [PATCH] Remove perspective hack

---
 shaders/flat.frag | 4 ++--
 shaders/flat.vert | 5 +++--
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/shaders/flat.frag b/shaders/flat.frag
index d9fc34b..8aed153 100644
--- a/shaders/flat.frag
+++ b/shaders/flat.frag
@@ -1,6 +1,6 @@
 #version 330 core
 
-in vec3 UV;
+noperspective in vec2 UV;
 in vec3 NORMAL;
 flat in vec3 LIGHT;
 
@@ -23,7 +23,7 @@ void main() {
     FragColor += vec4(material.color, 1.0);
   }
   if (material.usesTex) {
-    FragColor += texture(material.tex, UV.xy / UV.z);
+    FragColor += texture(material.tex, UV);
   }
   if (FragColor.w < material.alphaScissor) {
     discard;
diff --git a/shaders/flat.vert b/shaders/flat.vert
index 61792e1..8e1176f 100644
--- a/shaders/flat.vert
+++ b/shaders/flat.vert
@@ -8,7 +8,7 @@ uniform mat4 MODEL;
 uniform mat4 VIEW;
 uniform mat4 PROJECTION;
 
-out vec3 UV;
+noperspective out vec2 UV; // PSX use affine texture mapping
 out vec3 NORMAL;
 flat out vec3 LIGHT;
 
@@ -25,7 +25,8 @@ uniform DirectionalLight directionalLight;
 void main() {
   vec4 vertex = PROJECTION * VIEW * MODEL * vec4(pos, 1.0);
   gl_Position = vertex;
-  UV = vec3(uv * vertex.z, vertex.z);
+
+  UV = uv;
 
   NORMAL = (VIEW * MODEL * vec4(normal, 0.0)).xyz;