FixZBufferPrecision: fix lens flare being clipped out

resets znear before screen effects are drawn, kinda hacky but easier
than trying to reposition each screen effect

(wonder if this could be inverted so it'd only change znear temporarily while
stage is drawing, would solve any car clipping issues... no luck with that yet)

Author: emoose

Outrun2006Tweaks.ini

@@ -69,5 +69,4 @@ DisableVehicleLODs = true
 DisableStageCulling = true
 
 # FixZBufferPrecision: Fixes Z-Buffer precision issues, greatly reducing z-fighting and distant object drawing issues (eg. signs/buildings will have much less pop-in)
-#  Note: disabled by default as it may stop lens-flare effect from displaying, up to you which is more important
-FixZBufferPrecision = false
+FixZBufferPrecision = true

src/hooks_graphics.cpp

@@ -163,29 +163,57 @@ DisableVehicleLODs DisableVehicleLODs::instance;
 class FixZBufferPrecision : public Hook
 {
 	const static int CalcCameraMatrix_Addr = 0x84BD0;
+	const static int Clr_SceneEffect_Addr = 0xBE70;
 
-	inline static SafetyHookInline hook_orig = {};
+	inline static SafetyHookInline CalcCameraMatrix = {};
 
-	static void destination(EvWorkCamera* camera)
+	static inline bool allow_znear_override = true;
+	static void CalcCameraMatrix_dest(EvWorkCamera* camera)
 	{
 		// improve z-buffer precision by increasing znear
-		// game default is 0.1, which reduces precision of far objects massively, causing z-fighting and objects not drawing properly
+		// game default is 0.1 which reduces precision of far objects massively, causing z-fighting and objects not drawing properly
 
-		// only set znear to 1 if...
-		if ((camera->camera_mode_34A == 2 || camera->camera_mode_34A == 0) // ... in third-person or FPV
-			&& camera->camera_mode_timer_364 == 0 // ... not switching cameras
-			&& *Game::current_mode == STATE_GAME) // ... we're in main game state (not in STATE_START cutscene etc)
+		if (allow_znear_override)
 		{
-			camera->perspective_znear_BC = 0.99f; // 1.0 seems to cause sun flickering, but seems fine with 0.99
-		}
-		else
-		{
-			if (camera->camera_mode_timer_364 != 0 || *Game::current_mode != STATE_GAME)
-				camera->perspective_znear_BC = 0.1f; // set znear to 0.1 during camera switch / cutscene
+			// only set znear to 1 if...
+			if ((camera->camera_mode_34A == 2 || camera->camera_mode_34A == 0) // ... in third-person or FPV
+				&& camera->camera_mode_timer_364 == 0 // ... not switching cameras
+				&& *Game::current_mode == STATE_GAME) // ... we're in main game state (not in STATE_START cutscene etc)
+			{
+				camera->perspective_znear_BC = 1.0f;
+			}
 			else
-				camera->perspective_znear_BC = 0.3f; // 0.3 seems fine for in-car view, doesn't improve as much as 1.0f but still better than 0.1f
+			{
+				if (camera->camera_mode_timer_364 != 0 || *Game::current_mode != STATE_GAME)
+					camera->perspective_znear_BC = 0.1f; // set znear to 0.1 during camera switch / cutscene
+				else
+					camera->perspective_znear_BC = 0.3f; // 0.3 seems fine for in-car view, doesn't improve as much as 1.0f but still better than 0.1f
+			}
 		}
-		hook_orig.call(camera);
+		CalcCameraMatrix.call(camera);
+	}
+
+	// hook Clr_SceneEffect so we can reset camera z-near before screen effects are draw
+	inline static SafetyHookInline Clr_SceneEffect = {};
+	static void Clr_SceneEffect_dest(int a1)
+	{
+		FixZBufferPrecision::allow_znear_override = false;
+
+		EvWorkCamera* camera = Module::exe_ptr<EvWorkCamera>(0x39FE10);
+
+		float prev = camera->perspective_znear_BC;
+
+		// apply vanilla znear
+		camera->perspective_znear_BC = 0.05f; // game default = 0.1, but that causes lens flare to slightly clip, 0.05 allows it to fade properly
+		CalcCameraMatrix_dest(camera);
+
+		Clr_SceneEffect.call(a1);
+
+		// restore orig znear
+		camera->perspective_znear_BC = prev;
+		CalcCameraMatrix_dest(camera);
+
+		FixZBufferPrecision::allow_znear_override = true;
 	}
 
 public:
@@ -201,9 +229,12 @@ class FixZBufferPrecision : public Hook
 
 	bool apply() override
 	{
-		hook_orig = safetyhook::create_inline(Module::exe_ptr(CalcCameraMatrix_Addr), destination);
+		CalcCameraMatrix = safetyhook::create_inline(Module::exe_ptr(CalcCameraMatrix_Addr), CalcCameraMatrix_dest);
+		if (!CalcCameraMatrix)
+			return false;
 
-		return !!hook_orig;
+		Clr_SceneEffect = safetyhook::create_inline(Module::exe_ptr(Clr_SceneEffect_Addr), Clr_SceneEffect_dest);
+		return !!Clr_SceneEffect;
 	}
 
 	static FixZBufferPrecision instance;

src/plugin.hpp

@@ -52,7 +52,7 @@ namespace Settings
 	inline bool ScreenEdgeCullFix = true;
 	inline bool DisableVehicleLODs = true;
 	inline bool DisableStageCulling = true;
-	inline bool FixZBufferPrecision = false;
+	inline bool FixZBufferPrecision = true;
 }
 
 namespace Util