From f1a9f84f2443daef5a659d11063ef3256d80f177 Mon Sep 17 00:00:00 2001
From: xamidev <121681048+xamidev@users.noreply.github.com>
Date: Fri, 23 Aug 2024 13:05:53 +0200
Subject: [PATCH] Add: graphics mode terminal scrolling

---
 src/drivers/framebuffer.c | 38 ++++++++++++++++++++++++++++++++++
 src/drivers/framebuffer.h |  1 +
 src/kernel/kmain.c        | 11 +++++++---
 src/kernel/system.c       | 21 +++++++++++++++++++
 src/kernel/system.h       |  1 +
 src/libc/stdio.c          | 43 ++++++++++++++-------------------------
 src/libc/stdio.h          |  1 -
 src/programs/misc.c       |  3 ++-
 8 files changed, 86 insertions(+), 33 deletions(-)

diff --git a/src/drivers/framebuffer.c b/src/drivers/framebuffer.c
index 02687bd..922573e 100644
--- a/src/drivers/framebuffer.c
+++ b/src/drivers/framebuffer.c
@@ -1,6 +1,7 @@
 #include "../libc/stdint.h"
 #include "framebuffer.h"
 #include "serial.h"
+#include "../kernel/system.h"
 
 //extern uint32_t *g_framebuffer;
 
@@ -53,3 +54,40 @@ void draw_char(unsigned short int c, int cx, int cy, uint32_t fg, uint32_t bg)
 		offs += scanline;
 	}
 }
+
+void scroll()
+{
+	serial_printf(3, "Scrolling...\r");
+	uint32_t bg_color = 0x00000000;
+	PSF_font *font = (PSF_font*)&_binary_include_fonts_UniCyr_8x16_psf_start;
+	
+	int line_size = font->height * scanline;
+	int framebuffer_size = scanline * font->height * (1080/font->height);
+
+	// Erasing first line
+	for (uint32_t y=0; y<font->height; y++)
+	{
+		for (uint32_t x=0; x<scanline/sizeof(PIXEL); x++)
+		{
+			*((PIXEL*)(framebuffer + y * scanline + x * sizeof(PIXEL))) = bg_color;
+		}
+	}
+
+	// Moving all lines up by 1 line
+	for (int y=1; y<(framebuffer_size/line_size); y++)
+	{
+		void* src = framebuffer + y*line_size;
+		void* dst = framebuffer + (y-1)*line_size;
+		memmove(dst, src, line_size);
+	}
+
+	// Erasing last line
+	int last_line_start = (framebuffer_size/line_size-1) * line_size;
+	for (uint32_t y=0; y<font->height; y++)
+	{
+		for (uint32_t x=0; x<scanline/sizeof(PIXEL); x++)
+		{
+			*((PIXEL*)(framebuffer + last_line_start + y * scanline + x * sizeof(PIXEL))) = bg_color;
+		}
+	}
+}
diff --git a/src/drivers/framebuffer.h b/src/drivers/framebuffer.h
index f154f31..5a2a8ff 100644
--- a/src/drivers/framebuffer.h
+++ b/src/drivers/framebuffer.h
@@ -26,5 +26,6 @@ typedef struct {
 //extern const unsigned char font[512][64];
 void putpixel(uint32_t* fb, int pitch, int bpp, int x, int y, uint32_t color); 
 void draw_char(unsigned short int c, int cx, int cy, uint32_t fg, uint32_t bg);
+void scroll();
 
 #endif
diff --git a/src/kernel/kmain.c b/src/kernel/kmain.c
index ca81b11..5aba0fb 100644
--- a/src/kernel/kmain.c
+++ b/src/kernel/kmain.c
@@ -77,9 +77,9 @@ serial_printf(3, "Framebuffer BPP: %u\r\n", fb_info->framebuffer_bpp);
         uint32_t pitch = fb_info->framebuffer_pitch;
         uint32_t bpp = fb_info->framebuffer_bpp;
 
-	//8x16 font padded with 1 for each char = 9px/char
-	VGA_WIDTH = width/9;
-	VGA_HEIGHT = height/9;
+	//8x16 font, not padded 
+	VGA_WIDTH = width/8;
+	VGA_HEIGHT = height/16;
 
 	scanline = width * (bpp/8);	
 
@@ -114,6 +114,11 @@ serial_printf(3, "Framebuffer BPP: %u\r\n", fb_info->framebuffer_bpp);
     } 
     */
 
+    for (int i=0; i<100; i++)
+    {
+	printf("%d\n", i);
+    }
+
     //colorputs("Wow, such colorful output!", green, blue);
 
     colorputs(ascii_title, green, black);
diff --git a/src/kernel/system.c b/src/kernel/system.c
index 78f050e..36594da 100644
--- a/src/kernel/system.c
+++ b/src/kernel/system.c
@@ -8,6 +8,27 @@ void *memset(void *dest, char val, size_t count)
 	return dest;
 }
 
+void *memmove(void* dest, const void* src, size_t n)
+{
+	unsigned char* d = (unsigned char*)dest;
+	const unsigned char* s = (const unsigned char*)src;
+
+	if (d < s)
+	{
+		for (size_t i=0; i<n; i++)
+		{
+			d[i] = s[i];
+		}
+	} else {
+		for (size_t i=n; i>0; i--)
+		{
+			d[i-1] = s[i-1];
+		}
+	}
+
+	return dest;
+}
+
 void panic()
 {
 	for (;;);	
diff --git a/src/kernel/system.h b/src/kernel/system.h
index 86749e6..874cf19 100644
--- a/src/kernel/system.h
+++ b/src/kernel/system.h
@@ -6,6 +6,7 @@
 typedef int size_t;
 
 void *memset(void *dest, char val, size_t count);
+void *memmove(void* dest, const void* src, size_t n);
 
 struct regs
 {
diff --git a/src/libc/stdio.c b/src/libc/stdio.c
index 080da3d..932af77 100644
--- a/src/libc/stdio.c
+++ b/src/libc/stdio.c
@@ -4,6 +4,7 @@
 #include "stdint.h"
 #include "../kernel/system.h"
 #include "../drivers/framebuffer.h"
+#include "../drivers/serial.h"
 
 extern uint32_t* framebuffer;
 extern uint32_t VGA_WIDTH; 
@@ -35,32 +36,6 @@ void clear(void)
   move_cursor(0, 0);
 }
 
-void scroll(int lines)
-{
-  if (lines <= 0 || (unsigned int)lines >= VGA_HEIGHT) return;
-
-  for (unsigned int y = 0; y < VGA_HEIGHT-lines; y++)
-  {
-    for (unsigned int x = 0; x < VGA_WIDTH; x++)
-    {
-      //putchar(getchar(x, y+lines), x, y, white, black);
-    }
-  }
-
-  for (unsigned int y = VGA_HEIGHT-lines; y<VGA_HEIGHT; y++)
-  {
-    for (unsigned int x = 0; x < VGA_WIDTH; x++)
-    {
-      //putchar(' ', x, y, black, black);
-    }
-  }
-
-  VGA_Y -= lines;
-  if ((int)VGA_Y < 0) {
-	  VGA_Y = 0;
-  }
-}
-
 void putc(char c)
 {
   switch(c)
@@ -101,7 +76,12 @@ void putc(char c)
     VGA_Y++;
     VGA_X = 0;
   }
-  if (VGA_Y >= VGA_HEIGHT) scroll(1);
+  if (VGA_Y >= VGA_HEIGHT) 
+  {
+	serial_printf(3, "VGA_Y=%d, VGA_HEIGHT=%d: Scrolling...\r", VGA_Y, VGA_HEIGHT);
+	scroll();
+  	VGA_Y = VGA_HEIGHT - 1;
+  }	  
 
   move_cursor(VGA_X, VGA_Y);
 }
@@ -131,7 +111,14 @@ void colorputc(char c, uint32_t fg, uint32_t bg)
     VGA_Y++;
     VGA_X = 0;
   }
-  if (VGA_Y >= VGA_HEIGHT) scroll(1);
+
+  if (VGA_Y >= VGA_HEIGHT) 
+  {
+	serial_printf(3, "VGA_Y=%d, VGA_HEIGHT=%d: Scrolling...\r", VGA_Y, VGA_HEIGHT);
+	scroll();
+  	VGA_Y = VGA_HEIGHT - 1;
+  }	
+
   move_cursor(VGA_X, VGA_Y);
 }
 
diff --git a/src/libc/stdio.h b/src/libc/stdio.h
index b8ac4be..0b4883e 100644
--- a/src/libc/stdio.h
+++ b/src/libc/stdio.h
@@ -19,7 +19,6 @@ void colorputs(const char* str, uint32_t fg, uint32_t bg);
 void putcolor(int x, int y, unsigned int color);
 char getchar(int x, int y);
 unsigned int getcolor(int x, int y);
-void scroll(int lines);
 void putc(char c);
 void colorputc(char c, uint32_t fg, uint32_t bg);
 
diff --git a/src/programs/misc.c b/src/programs/misc.c
index 93fd47f..32b24c1 100644
--- a/src/programs/misc.c
+++ b/src/programs/misc.c
@@ -3,6 +3,7 @@
 #include "../libc/stdio.h"
 #include "../kernel/system.h"
 #include "../libc/string.h"
+#include "../drivers/framebuffer.h"
 
 // Print a rainbow colorful text for testing
 
@@ -29,7 +30,7 @@ void program_rainbow()
 
 void program_clear()
 {	
-	for (int i=0; i<ROWS; i++) scroll(1);
+	for (int i=0; i<ROWS; i++) scroll();
 }
 
 // Get uptime in ticks