4 files changed, 76 insertions, 20 deletions

diff --git a/kernel/Helpers/globalVars.hpp b/kernel/Helpers/globalVars.hpp
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/kernel/Helpers/globalVars.hpp
diff --git a/kernel/Helpers/memPrint.cpp b/kernel/Helpers/memPrint.cpp
index f6cc397..179b821 100644
--- a/kernel/Helpers/memPrint.cpp
+++ b/kernel/Helpers/memPrint.cpp
@@ -1,5 +1,7 @@
 #include "./memPrint.hpp"
 
+
+
 //Constructor
 memPrint::memPrint(){
 
@@ -21,14 +23,28 @@ memPrint::~memPrint(){
 
 //Move cursor
 void memPrint::updateCursor(){
+
+
+    //Update X axis
     this->m_cursorX++;
 
-    if(this->m_cursorX > MAXCURSORX){
+    //Check X value
+    if(this->m_cursorX >= MAXCURSORX){
+
+        //If X is out of the screen
         this->m_cursorX=0;
+
+        //Update Y
         this->m_cursorY++;
 
-        if(this->m_cursorY > MAXCURSORY){
-            //Scroll screen
+        //Check Y value
+        if(this->m_cursorY >= MAXCURSORY){
+
+            //If Y is out of the screen
+            this->scrollUp(1);
+
+            //Decrease Y value
+            this->m_cursorY--;
         }
 
 
@@ -37,35 +53,73 @@ void memPrint::updateCursor(){
 
 }
 
+//Change character background color
 void memPrint::setBackground(colorBios color){
     u8 newColor= (color << 4);
     this->m_colors= newColor | ((this->m_colors << 4) >> 4);
 }
 
+//Change character color
 void memPrint::setForeground(colorBios color){
     u8 newColor= color;
     this->m_colors= newColor | ((this->m_colors >> 4) << 4);
 }
 
 //Print a char
-
 void memPrint::putChar(u8 character){
 
-    char *adress= ((char *) MEMPRINTSTARTADR) + (this->m_cursorX * 2) + (this->m_cursorY * 80 * 2);
+    //Get the adresse with the cursor position
+    char *adress= ((char *) MEMPRINTSTARTADR) + (this->m_cursorX * 2) + (this->m_cursorY * MAXCURSORX * 2);
 
+    //Copy the character
     *adress=character;
 
+    //Copy his attribute
     adress++;
-
     *adress=this->m_colors;
 
+    //Update cursor position
     this->updateCursor();
 
 }
 
+
+//Print a char*
 void memPrint::print(char *str){
     while(*str!=0x0){
         this->putChar(*str);
         str++;
     }
 }
+
+//Clear the screen
+void memPrint::clear(){
+    this->scrollUp(MAXCURSORY);
+}
+
+//Scroll up "number" times
+void memPrint::scrollUp(u8 number){
+
+    //Get number of adress (char & his attribute) to scroll
+    int nbAdrToScroll=number*MAXCURSORX*2;
+
+
+    //Scroll all of the characters and attributes
+    for(int i=0;i!=MAXCURSORX*2*MAXCURSORY;i++){
+
+        //Get source character or attribute
+        char* source=(((char *)MEMPRINTSTARTADR) + i);
+
+        //Get destination character or attribute
+        char* dest=source-nbAdrToScroll;
+
+        //Check if destination is out of the screen
+        if(dest >= (char *)MEMPRINTSTARTADR)
+            *dest=*source;
+
+        //Remove data from source
+        *source=0x0;
+
+    }
+
+}
diff --git a/kernel/Helpers/memPrint.hpp b/kernel/Helpers/memPrint.hpp
index 437d6cb..19a6708 100644
--- a/kernel/Helpers/memPrint.hpp
+++ b/kernel/Helpers/memPrint.hpp
@@ -8,6 +8,9 @@
 #define MAXCURSORX 80
 #define MAXCURSORY 25
 
+
+
+
 //Define the bios color
 enum colorBios{
 
@@ -67,6 +70,12 @@ class memPrint{
 		//Print
         void print(char *str);
 
+        //Scroll up
+        void scrollUp(u8 number);
+
+        //Clear screen
+        void clear();
+
 };
 
 #endif
diff --git a/kernel/main.cpp b/kernel/main.cpp
index 9cd9875..0dec7e0 100644
--- a/kernel/main.cpp
+++ b/kernel/main.cpp
@@ -3,24 +3,17 @@
 #include "./Helpers/memPrint.hpp"
 
 
-//----- PiegOS kernel main -----
-int  main(){
+//----- Global Definition -----
+memPrint VideoRam;  //Used to print data on screen
+//-----------------------------
 
-    //Test print a char
-	/*char* letter=(char*)0xB8A00;
-	*letter='H';
-	letter++;
-	*letter=(GREEN << 4) | BLUE;*/
 
-    memPrint VideoRam;
 
+//----- PiegOS kernel main -----
+int  main(){
 
-    VideoRam.print("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa");
-    VideoRam.print("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa");
-    VideoRam.print("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa");
-    VideoRam.print("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa");
-    VideoRam.print("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa");
-    VideoRam.print("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa");
+    //Welcome
+    VideoRam.print("Welcome to PiegOS");
 
     //Infinite loop
 	while(1);