From 8f6ee75c381e9e0f8078083220e8d0a6af4a9b2c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Cl=C3=A9ment=20Le=20Bihan?= <clement.lebihan773@gmail.com>
Date: Sat, 3 Oct 2020 00:11:18 +0200
Subject: [PATCH] factorisation is done

---
 sources/PPU/Background.cpp | 75 +++++++++-----------------------------
 sources/PPU/Background.hpp |  2 +-
 2 files changed, 19 insertions(+), 58 deletions(-)

diff --git a/sources/PPU/Background.cpp b/sources/PPU/Background.cpp
index fa43841..05d9e5a 100644
--- a/sources/PPU/Background.cpp
+++ b/sources/PPU/Background.cpp
@@ -56,37 +56,20 @@ namespace ComSquare::PPU
 
 		tileData.raw = data;
 		palette = getPalette(tileData.palette);
-		// TODO explain X and Y and rethink the formula
 		// X horizontal
 		// Y vertical
 		graphicAddress = this->_tileSetAddress + (tileData.posY * 16 * this->_bpp * 8) + (tileData.posX * this->_bpp * 8);
 		for (int i = 0; i < this->_characterSize.y; i++) {
 			for (int j = 0; j < this->_characterSize.x; j++) {
-				/*if (index == 14) {
-					printf("cc");
-				}*/
 				reference = getPixelReferenceFromTile(graphicAddress, index);
 				color = getRealColor(palette[reference]);
 				if (tileData.tilePriority == this->priority) // reference 0 is considered as transparency
 					this->buffer[pos.x][pos.y] = (reference) ? color : 0;
-			/*	if (j == 7) {
-					index = -1;
-					// to go to the tile to the right
-					graphicAddress += 0x8 * this->_bpp;
-				}
-				if (index == 7 || this->_bpp == 8) {
-					index = -1;
-					graphicAddress += 2;
-				}*/
 				index++;
 				pos.x++;
 			}
-			//graphicAddress -= (0x8 * this->_bpp);
-			//index = 0;
 			pos.x -= this->_characterSize.x;
 			pos.y++;
-		//	if (i == 7)
-		//		graphicAddress += 0x100 - 8 * this->_bpp;
 		}
 	}
 
@@ -105,30 +88,31 @@ namespace ComSquare::PPU
 
 	uint8_t Background::getPixelReferenceFromTile(uint16_t tileAddress, uint8_t pixelIndex)
 	{
-		this->getCorrespondingBasicTileRowAndPixelIndex(&tileAddress, &pixelIndex);
-		return this->getPixelReferenceFromTileRow(tileAddress, pixelIndex);
+		uint8_t row = pixelIndex / this->_characterSize.x;
+		uint8_t column = pixelIndex % this->_characterSize.y;
+
+		if (row >= TILE_PIXEL_HEIGHT) {
+			tileAddress += 0x80 * this->_bpp;
+			row -= TILE_PIXEL_HEIGHT;
+		}
+		if (column >= TILE_PIXEL_WIDTH) {
+			tileAddress += 0x8 * this->_bpp;
+			column -= TILE_PIXEL_WIDTH;
+		}
+		// might not work with 8 bpp must check
+		tileAddress += this->_bpp * row;
+
+		return this->getPixelReferenceFromTileRow(tileAddress, column);
 	}
 
 	uint8_t Background::getPixelReferenceFromTileRow(uint16_t tileAddress, uint8_t pixelIndex)
 	{
-		//line by line for each pixel of the line
-		uint8_t highByte;
-		uint8_t lowByte;
+		uint8_t highByte = this->_vram->read_internal(tileAddress % VRAMSIZE);
+		uint8_t lowByte = this->_vram->read_internal((tileAddress + 1) % VRAMSIZE);
 		uint8_t secondHighByte;
 		uint8_t secondLowByte;
 		uint8_t result = 0;
-		uint8_t shift;
-		uint8_t rowNumber = pixelIndex / TILE_PIXEL_WIDTH;
-		// C000
-		//gérer le character size mauvais pour le retour de ligne
-
-		//pixelIndex -= rowNumber * TILE_PIXEL_WIDTH; //get the index relative to the row
-		//tileAddress += rowNumber * TILE_PIXEL_WIDTH * this->_bpp; // get row address
-
-		highByte = this->_vram->read_internal(tileAddress % VRAMSIZE);
-		lowByte = this->_vram->read_internal((tileAddress + 1) % VRAMSIZE);
-
-		shift = (TILE_PIXEL_WIDTH - 1U - pixelIndex);
+		uint8_t shift = (TILE_PIXEL_WIDTH - 1U - pixelIndex);
 
 		switch (this->_bpp) {
 		case 8:
@@ -175,27 +159,4 @@ namespace ComSquare::PPU
 	{
 		this->_characterSize = size;
 	}
-
-	void Background::getCorrespondingBasicTileRowAndPixelIndex(uint16_t *tileAddress, uint8_t *pixelIndex)
-	{
-		uint16_t tmpTileAddress = *tileAddress;
-		uint16_t tmpPixelIndex = *pixelIndex;
-
-		uint8_t row = tmpPixelIndex / this->_characterSize.x;
-		uint8_t column = tmpPixelIndex / this->_characterSize.y;
-
-		if (row >= TILE_PIXEL_HEIGHT) {
-			tmpTileAddress += 0x80 * this->_bpp;
-			row -= TILE_PIXEL_HEIGHT;
-		}
-		if (column >= TILE_PIXEL_WIDTH) {
-			tmpTileAddress += 0x8 * this->_bpp;
-			column -= TILE_PIXEL_WIDTH;
-		}
-		// might not work with 8 bpp must check
-		tmpTileAddress += this->_bpp * row;
-
-		*tileAddress = tmpTileAddress;
-		*pixelIndex = tmpPixelIndex;
-	}
 }
\ No newline at end of file
diff --git a/sources/PPU/Background.hpp b/sources/PPU/Background.hpp
index a7b9ad9..089bd2a 100644
--- a/sources/PPU/Background.hpp
+++ b/sources/PPU/Background.hpp
@@ -43,7 +43,7 @@ namespace ComSquare::PPU
 		//TODO support addr as the address of the start of the tile and index goes from 0 to 63 regardless of the bpp
 		uint8_t getPixelReferenceFromTileRow(uint16_t tileAddress, uint8_t pixelIndex);
 		uint8_t getPixelReferenceFromTile(uint16_t tileAddress, uint8_t pixelIndex);
-		void getCorrespondingBasicTileRowAndPixelIndex(uint16_t *tileAddress, uint8_t *pixelIndex);
+
 		//! @brief draw a tilemap 32x32 starting at baseAddress
 		void drawBasicTileMap(uint16_t baseAddress, Vector2<int> offset);
 	public: