From 44b48ffacd36107a810695b02b214e9de0a86342 Mon Sep 17 00:00:00 2001
From: Lilaa3 <87947656+Lilaa3@users.noreply.github.com>
Date: Mon, 18 Sep 2023 15:18:35 +0100
Subject: [PATCH] Important Culling Fixes (#666)

* Culling fix

Precison of half fov horizontal being equal to or above 2 leads to many issues. using 1.5 would break rt64 and other emulators with ultra widescreen.
Vertical culling will be disabled by default until 3.0

* Improved emu checks and naming

* Comment changes

* Small typo fix
---
 include/config/config_graphics.h | 10 ++++++----
 src/game/rendering_graph_node.c  | 26 ++++++++++++--------------
 2 files changed, 18 insertions(+), 18 deletions(-)

diff --git a/include/config/config_graphics.h b/include/config/config_graphics.h
index 03d8ff11..33f52a13 100644
--- a/include/config/config_graphics.h
+++ b/include/config/config_graphics.h
@@ -129,14 +129,16 @@
 
 
 /**
- * Limits the horizontal fov on emulator like on console. May break viewport widescreen hacks.
+ * May break viewport widescreen hacks.
+ * When this is disabled, the culling will only be skipped according to the NO_CULLING_EMULATOR_BLACKLIST.
  */
-// #define HORIZONTAL_CULLING_ON_EMULATOR
+// #define CULLING_ON_EMULATOR
 
 /**
- * Makes objects bellow the screen be culled.
+ * Makes objects below the screen be culled. 
+ * NOTE: Vanilla objects do not account for vertical culling.
  */
-#define VERTICAL_CULLING
+// #define VERTICAL_CULLING
 
 /**
  * If the first command of an object´s geolayout is not GEO_CULLING_RADIUS, DEFAULT_CULLING_RADIUS
diff --git a/src/game/rendering_graph_node.c b/src/game/rendering_graph_node.c
index c5d5c97b..295d6c4e 100644
--- a/src/game/rendering_graph_node.c
+++ b/src/game/rendering_graph_node.c
@@ -567,27 +567,15 @@ void geo_process_perspective(struct GraphNodePerspective *node) {
         sAspectRatio = 4.0f / 3.0f; // 1.33333f
 #endif
 
-        // The reason this is not divided as an integer is to prevent an integer division.
-        f32 vHalfFov = ( (f32) ((node->fov * 4096) + 8192) ) / 45.f;
+        f32 vHalfFov = ( ((node->fov * 4096.f) + 8192.f) ) / 45.f;
 
         // We need to account for aspect ratio changes by multiplying by the widescreen horizontal stretch 
         // (normally 1.775).
-        f32 hHalfFov = vHalfFov * sAspectRatio;
-
-        node->halfFovHorizontal = tans(hHalfFov);
+        node->halfFovHorizontal = tans(vHalfFov * sAspectRatio);
 
 #ifdef VERTICAL_CULLING
         node->halfFovVertical = tans(vHalfFov);
 #endif
-
-#ifndef HORIZONTAL_CULLING_ON_EMULATOR
-        // If an emulator is detected, use a large value for the half fov 
-        // horizontal value to account for viewport widescreen hacks.
-
-        if(!(gEmulator & EMU_CONSOLE)){
-            node->halfFovHorizontal = 9999.0f;
-        }
-#endif
     
         guPerspective(mtx, &perspNorm, node->fov, sAspectRatio, node->near / WORLD_SCALE, node->far / WORLD_SCALE, 1.0f);
         gSPPerspNormalize(gDisplayListHead++, perspNorm);
@@ -1065,6 +1053,9 @@ void geo_process_shadow(struct GraphNodeShadow *node) {
  *
  * Since (0,0,0) is unaffected by rotation, columns 0, 1 and 2 are ignored.
  */
+
+#define NO_CULLING_EMULATOR_BLACKLIST (EMU_CONSOLE | EMU_WIIVC | EMU_ARES | EMU_SIMPLE64 | EMU_CEN64)
+
 s32 obj_is_in_view(struct GraphNodeObject *node) {
     struct GraphNode *geo = node->sharedChild;
 
@@ -1089,6 +1080,13 @@ s32 obj_is_in_view(struct GraphNodeObject *node) {
         return FALSE;
     }
 
+#ifndef CULLING_ON_EMULATOR
+    // If an emulator is detected, skip any other culling.
+    if(!(gEmulator & NO_CULLING_EMULATOR_BLACKLIST)){
+        return TRUE;
+    }
+#endif
+
 #ifdef VERTICAL_CULLING
     f32 vScreenEdge = -cameraToObjectDepth * gCurGraphNodeCamFrustum->halfFovVertical;