From 647fb43ccd04844c49df84dc1b469b5bb9384693 Mon Sep 17 00:00:00 2001
From: UnknownShadow200 <unknownshadow200@gmail.com>
Date: Tue, 11 Mar 2025 07:37:01 +1100
Subject: [PATCH] PS1: Fix launcher not drawing in pcsx-redux software mode

---
 misc/ps1/ps1defs.h | 6 ++++++
 src/Window_PS1.c   | 4 ++++
 2 files changed, 10 insertions(+)

diff --git a/misc/ps1/ps1defs.h b/misc/ps1/ps1defs.h
index 06726aadf..a23ded427 100644
--- a/misc/ps1/ps1defs.h
+++ b/misc/ps1/ps1defs.h
@@ -6,6 +6,7 @@ enum dma_chrc_CMD {
 	CHRC_FROM_RAM      = (1 << 0),
 	CHRC_DIR_DECREMENT = (1 << 1),
 	CHRC_MODE_SLICE    = (1 << 9),
+	CHRC_MODE_CHAIN    = (1 << 10),
 	CHRC_BEGIN_XFER    = (1 << 24),
 	CHRC_NO_DREQ_WAIT  = (1 << 28),
 };
@@ -21,6 +22,7 @@ enum gp0_cmd_type {
 	GP0_CMD_CLEAR_VRAM_CACHE = 0x01000000,
 	GP0_CMD_TRANSFER_TO_VRAM = 0xA0000000,
 	GP0_CMD_POLYGON          = 0x20000000,
+	GP0_CMD_RECTANGLE        = 0x60000000,
 };
 
 enum gp0_polycmd_flags {
@@ -29,6 +31,10 @@ enum gp0_polycmd_flags {
 	POLY_CMD_SEMITRNS = 1u << 25,
 };
 
+enum gp0_rectcmd_flags {
+	RECT_CMD_1x1 = 1u << 27,
+};
+
 enum gp1_cmd_type {
 	GP1_CMD_DISPLAY_ACTIVE   = 0x03000000,
 	GP1_CMD_DMA_MODE         = 0x04000000,
diff --git a/src/Window_PS1.c b/src/Window_PS1.c
index e97fee398..cf25c293a 100644
--- a/src/Window_PS1.c
+++ b/src/Window_PS1.c
@@ -212,6 +212,10 @@ void Window_AllocFramebuffer(struct Bitmap* bmp, int width, int height) {
 }
 
 void Window_DrawFramebuffer(Rect2D r, struct Bitmap* bmp) {
+	// Fix not drawing in pcsx-redux software mode
+	GPU_GP0 = GP0_CMD_RECTANGLE | RECT_CMD_1x1;
+	GPU_GP0 = (0 << 16) | 0;
+
 	Gfx_TransferToVRAM(0, 0, SCREEN_XRES, SCREEN_YRES, bmp->scan0);
 }