From 9ed80467762a5024f7ba04e9fb384faceca35c29 Mon Sep 17 00:00:00 2001
From: notaz <notasas@gmail.com>
Date: Wed, 25 Oct 2023 01:36:42 +0300
Subject: [PATCH] gpulib: trust game's centering based on a database

libretro/pcsx_rearmed#160
---
 frontend/plugin.c       |  3 +++
 frontend/plugin_lib.h   |  1 +
 libpcsxcore/database.c  | 11 ++++++++++-
 libpcsxcore/psxcommon.h |  3 ++-
 libpcsxcore/psxhw.c     |  2 +-
 plugins/gpulib/gpu.c    |  6 +++++-
 plugins/gpulib/gpu.h    |  3 ++-
 7 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/frontend/plugin.c b/frontend/plugin.c
index 3683b500..88d756eb 100644
--- a/frontend/plugin.c
+++ b/frontend/plugin.c
@@ -264,6 +264,9 @@ void plugin_call_rearmed_cbs(void)
 	extern void *hGPUDriver;
 	void (*rearmed_set_cbs)(const struct rearmed_cbs *cbs);
 
+	pl_rearmed_cbs.screen_centering_type_default =
+		Config.hacks.gpu_centering ? C_INGAME : C_AUTO;
+
 	rearmed_set_cbs = SysLoadSym(hGPUDriver, "GPUrearmedCallbacks");
 	if (rearmed_set_cbs != NULL)
 		rearmed_set_cbs(&pl_rearmed_cbs);
diff --git a/frontend/plugin_lib.h b/frontend/plugin_lib.h
index 76220978..2ac49f2c 100644
--- a/frontend/plugin_lib.h
+++ b/frontend/plugin_lib.h
@@ -112,6 +112,7 @@ struct rearmed_cbs {
 	// misc
 	int gpu_caps;
 	int screen_centering_type;
+	int screen_centering_type_default;
 	int screen_centering_x;
 	int screen_centering_y;
 };
diff --git a/libpcsxcore/database.c b/libpcsxcore/database.c
index a68fe4f3..2acd6754 100644
--- a/libpcsxcore/database.c
+++ b/libpcsxcore/database.c
@@ -39,6 +39,14 @@ static const char * const gpu_busy_hack_db[] =
 	"SLPS01919", "SLPS01920",
 };
 
+static const char * const gpu_centering_hack_db[] =
+{
+	/* Gradius Gaiden */
+	"SLPM86042", "SLPM86103", "SLPM87323",
+	/* Sexy Parodius */
+	"SLPM86009",
+};
+
 #define HACK_ENTRY(var, list) \
 	{ #var, &Config.hacks.var, list, ARRAY_SIZE(list) }
 
@@ -53,7 +61,8 @@ hack_db[] =
 {
 	HACK_ENTRY(cdr_read_timing, cdr_read_hack_db),
 	HACK_ENTRY(gpu_slow_list_walking, gpu_slow_llist_db),
-	HACK_ENTRY(gpu_busy_hack, gpu_busy_hack_db),
+	HACK_ENTRY(gpu_busy, gpu_busy_hack_db),
+	HACK_ENTRY(gpu_centering, gpu_centering_hack_db),
 };
 
 static const struct
diff --git a/libpcsxcore/psxcommon.h b/libpcsxcore/psxcommon.h
index f978a583..09fb39a4 100644
--- a/libpcsxcore/psxcommon.h
+++ b/libpcsxcore/psxcommon.h
@@ -150,7 +150,8 @@ typedef struct {
 	struct {
 		boolean cdr_read_timing;
 		boolean gpu_slow_list_walking;
-		boolean gpu_busy_hack;
+		boolean gpu_busy;
+		boolean gpu_centering;
 	} hacks;
 } PcsxConfig;
 
diff --git a/libpcsxcore/psxhw.c b/libpcsxcore/psxhw.c
index 832e6d7d..b8ca1996 100644
--- a/libpcsxcore/psxhw.c
+++ b/libpcsxcore/psxhw.c
@@ -42,7 +42,7 @@ void psxHwReset() {
 	cdrReset();
 	psxRcntInit();
 	HW_GPU_STATUS = SWAP32(0x10802000);
-	psxHwReadGpuSRptr = Config.hacks.gpu_busy_hack
+	psxHwReadGpuSRptr = Config.hacks.gpu_busy
 		? psxHwReadGpuSRbusyHack : psxHwReadGpuSR;
 }
 
diff --git a/plugins/gpulib/gpu.c b/plugins/gpulib/gpu.c
index f0767745..2ac36c1b 100644
--- a/plugins/gpulib/gpu.c
+++ b/plugins/gpulib/gpu.c
@@ -74,7 +74,10 @@ static noinline void update_width(void)
   int hres = hres_all[(gpu.status >> 16) & 7];
   int pal = gpu.status & PSX_GPU_STATUS_PAL;
   int sw = gpu.screen.x2 - gpu.screen.x1;
+  int type = gpu.state.screen_centering_type;
   int x = 0, x_auto;
+  if (type == C_AUTO)
+    type = gpu.state.screen_centering_type_default;
   if (sw <= 0)
     /* nothing displayed? */;
   else {
@@ -83,7 +86,7 @@ static noinline void update_width(void)
     x = (x + 1) & ~1;   // blitter limitation
     sw /= hdiv;
     sw = (sw + 2) & ~3; // according to nocash
-    switch (gpu.state.screen_centering_type) {
+    switch (type) {
     case C_INGAME:
       break;
     case C_MANUAL:
@@ -919,6 +922,7 @@ void GPUrearmedCallbacks(const struct rearmed_cbs *cbs)
   gpu.state.frame_count = cbs->gpu_frame_count;
   gpu.state.allow_interlace = cbs->gpu_neon.allow_interlace;
   gpu.state.enhancement_enable = cbs->gpu_neon.enhancement_enable;
+  gpu.state.screen_centering_type_default = cbs->screen_centering_type_default;
   if (gpu.state.screen_centering_type != cbs->screen_centering_type
       || gpu.state.screen_centering_x != cbs->screen_centering_x
       || gpu.state.screen_centering_y != cbs->screen_centering_y) {
diff --git a/plugins/gpulib/gpu.h b/plugins/gpulib/gpu.h
index bf3d28a9..ab1d23a7 100644
--- a/plugins/gpulib/gpu.h
+++ b/plugins/gpulib/gpu.h
@@ -89,7 +89,8 @@ struct psx_gpu {
     } last_list;
     uint32_t last_vram_read_frame;
     uint32_t w_out_old, h_out_old, status_vo_old;
-    int screen_centering_type; // 0 - auto, 1 - game conrolled, 2 - manual
+    short screen_centering_type;
+    short screen_centering_type_default;
     int screen_centering_x;
     int screen_centering_y;
   } state;
-- 
2.39.5