From a1bda5cfa3495cd478b1a79aaa43b0d3813a1c92 Mon Sep 17 00:00:00 2001
From: Francisco Javier Trujillo Mata <fjtrujy@gmail.com>
Date: Tue, 22 Aug 2023 19:33:18 +0200
Subject: [PATCH] Creating an example of using a texture with Clut

---
 examples/Makefile      |   1 +
 examples/clut/Makefile |  16 +++++++
 examples/clut/clut.c   | 101 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 118 insertions(+)
 create mode 100644 examples/clut/Makefile
 create mode 100644 examples/clut/clut.c

diff --git a/examples/Makefile b/examples/Makefile
index 1f4b2ae..116a162 100644
--- a/examples/Makefile
+++ b/examples/Makefile
@@ -15,6 +15,7 @@ SUBDIRS += atlas
 SUBDIRS += basic
 SUBDIRS += bigtex
 SUBDIRS += coverflow
+SUBDIRS += clut
 SUBDIRS += cube
 SUBDIRS += fb
 SUBDIRS += fhdbg
diff --git a/examples/clut/Makefile b/examples/clut/Makefile
new file mode 100644
index 0000000..cb5d851
--- /dev/null
+++ b/examples/clut/Makefile
@@ -0,0 +1,16 @@
+#  ____     ___ |    / _____ _____
+# |  __    |    |___/    |     |
+# |___| ___|    |    \ __|__   |     gsKit Open Source Project.
+# ----------------------------------------------------------------------
+# Copyright 2004 - Chris "Neovanglist" Gilbert <Neovanglist@LainOS.org>
+# Licenced under Academic Free License version 2.0
+# Review gsKit README & LICENSE files for further details.
+#
+# examples/clut/Makefile - Makefile for "clut" example.
+#
+
+EE_BIN  = clut.elf
+EE_OBJS = clut.o
+
+include ../../Makefile.pref
+include ../Makefile.global
diff --git a/examples/clut/clut.c b/examples/clut/clut.c
new file mode 100644
index 0000000..f0ca461
--- /dev/null
+++ b/examples/clut/clut.c
@@ -0,0 +1,101 @@
+//  ____     ___ |    / _____ _____
+// |  __    |    |___/    |     |
+// |___| ___|    |    \ __|__   |     gsKit Open Source Project.
+// ----------------------------------------------------------------------
+// Copyright 2004 - Chris "Neovanglist" Gilbert <Neovanglist@LainOS.org>
+// Licenced under Academic Free License version 2.0
+// Review gsKit README & LICENSE files for further details.
+//
+// textures.c - Example demonstrating gsKit texture operation.
+//
+
+#include <stdio.h>
+#include <malloc.h>
+
+#include <gsKit.h>
+#include <dmaKit.h>
+#include <gsToolkit.h>
+#include <gsInline.h>
+#include <gsTexture.h>
+
+#define CLUT_SIZE 256
+#define TEXTURE_WIDTH 320
+#define TEXTURE_HEIGHT 240
+
+int main(int argc, char *argv[])
+{
+	GSGLOBAL *gsGlobal;
+	GSTEXTURE tex;
+	uint32_t i, j, offset;
+	uint32_t totalVertices = 2;
+	uint64_t White = GS_SETREG_RGBAQ(0xFF,0xFF,0xFF,0x00,0x00);
+	gs_rgbaq color = color_to_RGBAQ(0x80, 0x80, 0x80, 0x80, 0);
+
+	gsGlobal = gsKit_init_global();
+
+	gsGlobal->PSM = GS_PSM_CT24;
+	gsGlobal->PSMZ = GS_PSMZ_16S;
+
+	dmaKit_init(D_CTRL_RELE_OFF,D_CTRL_MFD_OFF, D_CTRL_STS_UNSPEC,
+		    D_CTRL_STD_OFF, D_CTRL_RCYC_8, 1 << DMA_CHANNEL_GIF);
+
+	// Initialize the DMAC
+	dmaKit_chan_init(DMA_CHANNEL_GIF);
+
+	gsKit_init_screen(gsGlobal);
+	gsKit_TexManager_init(gsGlobal);
+	gsKit_mode_switch(gsGlobal, GS_ONESHOT);
+
+	tex.Width = TEXTURE_WIDTH;
+	tex.Height = TEXTURE_HEIGHT;
+	tex.PSM = GS_PSM_T8;
+	tex.ClutPSM = GS_PSM_CT32;
+	tex.Clut = memalign(128, gsKit_texture_size_ee(CLUT_SIZE, 1, tex.ClutPSM));
+	tex.Mem = memalign(128, gsKit_texture_size_ee(tex.Width, tex.Height, tex.PSM));
+
+	printf("Tex VRAM Range = 0x%X - 0x%X\n",tex.Vram, tex.Vram +gsKit_texture_size(tex.Width, tex.Height, tex.PSM) - 1);
+
+	gsKit_set_clamp(gsGlobal, GS_CMODE_CLAMP);
+
+	// initialize texture
+	uint8_t *tex256 = (uint8_t*)tex.Mem;
+	for (j = 0; j < tex.Height; ++j) {
+		for (i = 0; i < tex.Width; ++i) {
+			tex256[i + j * tex.Width] = j ^ i;
+		}
+	}
+	
+	GSPRIMUVPOINT *verts = (GSPRIMUVPOINT*)malloc(sizeof(GSPRIMUVPOINT) * totalVertices);
+	verts[0].xyz2 = vertex_to_XYZ2(gsGlobal, 0, 0, 0);
+	verts[0].rgbaq = color;
+	verts[0].uv = vertex_to_UV(&tex, 0, 0);
+
+	verts[1].xyz2 = vertex_to_XYZ2(gsGlobal, gsGlobal->Width, gsGlobal->Height, 0);
+	verts[1].rgbaq = color;
+	verts[1].uv = vertex_to_UV(&tex, tex.Width, tex.Height);
+
+	offset = 0;
+
+	while(1) {
+		unsigned int* clut = tex.Clut;
+		for (i = 0; i < CLUT_SIZE; ++i) {
+			unsigned int j = (i + offset)&0xff;
+			*(clut++) = (j << 24)|(j << 16)|(j << 8)|(j);
+		}
+
+		gsKit_clear(gsGlobal, White);
+		gsKit_TexManager_invalidate(gsGlobal, &tex);
+		gsKit_TexManager_bind(gsGlobal, &tex);
+		gskit_prim_list_sprite_texture_uv_3d(gsGlobal, &tex, totalVertices, verts);
+		
+		gsKit_queue_exec(gsGlobal);
+		gsKit_sync_flip(gsGlobal);
+		gsKit_TexManager_nextFrame(gsGlobal);
+
+		offset++;
+	}
+
+	free(verts);
+
+	return 0;
+}