From 346b01be077b90dbe04f1318fdb1d607c2d5fd78 Mon Sep 17 00:00:00 2001
From: Gary Talent <gtalent2@gmail.com>
Date: Fri, 5 May 2017 18:54:13 -0500
Subject: [PATCH] Start on support for 4 bpp images

This may be all that's needed, but there seems to be another issue
causing the characters to look weird, though that's probably a
filesystem issue.
---
 build_rom.sh         |  4 ++--
 src/core/gba/gfx.cpp | 15 +++++++++++----
 src/tools/pack.cpp   | 18 ++++++++++++++++--
 3 files changed, 29 insertions(+), 8 deletions(-)

diff --git a/build_rom.sh b/build_rom.sh
index b6e1671d..a806294c 100755
--- a/build_rom.sh
+++ b/build_rom.sh
@@ -2,11 +2,11 @@
 
 set -e
 
-${DEVKITARM}/bin/padbin 32 build/gba-release/src/player/nostalgia.bin
 echo NOSTALGIA_MEDIA_HEADER_________ > media_header.txt
 
 oxfs format 32 1m nostalgia_media.oxfs
-./build/current/src/tools/nost-pack -fs nostalgia_media.oxfs -img charset.png -inode 1 -tiles 40 -c
+./build/current/src/tools/nost-pack -fs nostalgia_media.oxfs -img charset.png -inode 101 -tiles 40 -bpp 4 -c
 
+${DEVKITARM}/bin/padbin 32 build/gba-release/src/player/nostalgia.bin
 cat build/gba-release/src/player/nostalgia.bin media_header.txt nostalgia_media.oxfs > nostalgia.gba
 ${DEVKITARM}/bin/gbafix nostalgia.gba
diff --git a/src/core/gba/gfx.cpp b/src/core/gba/gfx.cpp
index 69b981a7..9ff6c8d1 100644
--- a/src/core/gba/gfx.cpp
+++ b/src/core/gba/gfx.cpp
@@ -129,12 +129,19 @@ ox::Error initGfx() {
 
 void initConsole() {
 	auto fs = (FileStore32*) findMedia();
+
+	GbaImageData imgData;
+	fs->read(101, __builtin_offsetof(GbaImageData, tileCount),
+	         sizeof(imgData.tileCount) + sizeof(imgData.bpp),
+	         &imgData.tileCount, nullptr);
+
 	REG_BG0CNT = (28 << 8) | 1;
-	REG_BG0CNT |= (1 << 7); // set to use 8 bits per pixel
+	if (imgData.bpp == 8) {
+		REG_BG0CNT |= (1 << 7); // set to use 8 bits per pixel
+	}
 	if (fs) {
-		FileStore32::FsSize_t readSize = 0;
-		fs->read(1, __builtin_offsetof(GbaImageData, tiles), 64 * 38, &TILE8_ADDR[0][1], nullptr);
-		fs->read(1, 0, 512, &MEM_PALLETE_BG[0], &readSize);
+		fs->read(101, __builtin_offsetof(GbaImageData, tiles), 64 * 38, &TILE8_ADDR[0][1], nullptr);
+		fs->read(101, __builtin_offsetof(GbaImageData, pal), 512, &MEM_PALLETE_BG[0], nullptr);
 	}
 }
 
diff --git a/src/tools/pack.cpp b/src/tools/pack.cpp
index 60d09e46..7de52069 100644
--- a/src/tools/pack.cpp
+++ b/src/tools/pack.cpp
@@ -64,6 +64,7 @@ int run(ClArgs args) {
 	QString argFsPath = args.getString("fs").c_str();
 	auto argCompact = args.getBool("c");
 	auto argTiles = args.getInt("tiles");
+	auto argBpp = args.getInt("bpp");
 
 	QImage src(argInPath);
 
@@ -71,13 +72,16 @@ int run(ClArgs args) {
 		if (argTiles == 0) {
 			argTiles = (src.width() * src.height()) / 64;
 		}
+		if (argBpp != 4 && argBpp != 8) {
+			argBpp = 8;
+		}
 
 		QMap<QRgb, int> colors;
 		const auto imgDataBuffSize = sizeof(GbaImageData) + 1 + argTiles * 64;
 		uint8_t imgDataBuff[imgDataBuffSize];
 		memset(&imgDataBuff, 0, imgDataBuffSize);
 		GbaImageData *id = (GbaImageData*) imgDataBuff;
-		id->bpp = 8;
+		id->bpp = argBpp;
 		id->tileCount = argTiles;
 		int colorId = 0;
 
@@ -87,11 +91,21 @@ int run(ClArgs args) {
 				auto destI = pointToIdx(src.width(), x, y);
 				if (destI <= argTiles * 64) {
 					auto c = src.pixel(x, y);
+					// assign color a color id for the palette
 					if (!colors.contains(c)) {
 						colors[c] = colorId;
 						colorId++;
 					}
-					id->tiles[destI] = colors[c];
+					// set pixel color
+					if (argBpp == 4) {
+						if (destI % 2) { // is odd number pixel
+							id->tiles[destI / 2] |= colors[c] << 4;
+						} else {
+							id->tiles[destI / 2] |= colors[c];
+						}
+					} else {
+						id->tiles[destI] = colors[c];
+					}
 				}
 			}
 		}