/*******************************************************************************
Copyright(C) Jonas 'Sortie' Termansen 2012.
This file is part of Sortix.
Sortix is free software: you can redistribute it and/or modify it under the
terms of the GNU General Public License as published by the Free Software
Foundation, either version 3 of the License, or (at your option) any later
version.
Sortix is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
details.
You should have received a copy of the GNU General Public License along with
Sortix. If not, see .
vgatextbuffer.cpp
An indexable text buffer with the VGA text mode framebuffer as backend.
*******************************************************************************/
#include
#include
#include
#include
#include
#include "vga.h"
#include "vgatextbuffer.h"
namespace Sortix {
VGATextBuffer::VGATextBuffer(uint16_t* vga, uint16_t* attr,
size_t width, size_t height)
{
this->vga = vga;
this->attr = attr;
this->width = width;
this->height = height;
cursorpos = {0, 0};
cursorenabled = true;
UpdateCursor();
}
VGATextBuffer::~VGATextBuffer()
{
}
static TextChar EntryToTextChar(uint16_t entry)
{
char c = entry & 0x00FF;
uint8_t vgacolor = entry >> 8U;
return TextChar{c, vgacolor};
}
static uint16_t CharToTextEntry(TextChar c)
{
return (uint16_t) c.c | (uint16_t) c.vgacolor << 8U;
}
bool VGATextBuffer::UsablePosition(TextPos pos) const
{
return pos.x < width && pos.y < height;
}
TextPos VGATextBuffer::CropPosition(TextPos pos) const
{
if ( width <= pos.x )
pos.x = width - 1;
if ( height <= pos.y )
pos.y = height -1;
return pos;
}
size_t VGATextBuffer::OffsetOfPos(TextPos pos) const
{
return pos.y * width + pos.x;
}
size_t VGATextBuffer::Width() const
{
return width;
}
size_t VGATextBuffer::Height() const
{
return height;
}
TextChar VGATextBuffer::GetChar(TextPos pos) const
{
if ( UsablePosition(pos) )
return EntryToTextChar(vga[OffsetOfPos(pos)]);
return {0, 0};
}
void VGATextBuffer::SetChar(TextPos pos, TextChar c)
{
if ( UsablePosition(pos) )
vga[OffsetOfPos(pos)] = CharToTextEntry(c);
}
uint16_t VGATextBuffer::GetCharAttr(TextPos pos) const
{
if ( UsablePosition(pos) )
return attr[OffsetOfPos(pos)];
return 0;
}
void VGATextBuffer::SetCharAttr(TextPos pos, uint16_t attrval)
{
if ( UsablePosition(pos) )
attr[OffsetOfPos(pos)] = attrval;
}
void VGATextBuffer::Scroll(ssize_t off, TextChar fillwith)
{
if ( !off )
return;
bool neg = 0 < off;
size_t absoff = off < 0 ? -off : off;
if ( height < absoff )
absoff = height;
TextPos scrollfrom = neg ? TextPos{0, absoff} : TextPos{0, 0};
TextPos scrollto = neg ? TextPos{0, 0} : TextPos{0, absoff};
TextPos fillfrom = neg ? TextPos{0, height-absoff} : TextPos{0, 0};
TextPos fillto = neg ? TextPos{width-1, height-1} : TextPos{width-1, absoff-1};
size_t scrollchars = width * (height-absoff);
Move(scrollto, scrollfrom, scrollchars);
Fill(fillfrom, fillto, fillwith, 0);
}
void VGATextBuffer::Move(TextPos to, TextPos from, size_t numchars)
{
size_t dest = OffsetOfPos(CropPosition(to));
size_t src = OffsetOfPos(CropPosition(from));
if ( dest < src )
for ( size_t i = 0; i < numchars; i++ )
vga[dest + i] = vga[src + i],
attr[dest + i] = attr[src + i];
else if ( src < dest )
for ( size_t i = 0; i < numchars; i++ )
vga[dest + numchars-1 - i] = vga[src + numchars-1 - i],
attr[dest + numchars-1 - i] = attr[src + numchars-1 - i];
}
void VGATextBuffer::Fill(TextPos from, TextPos to, TextChar fillwith,
uint16_t fillattr)
{
from = CropPosition(from);
to = CropPosition(to);
size_t start = OffsetOfPos(from);
size_t end = OffsetOfPos(to);
size_t entry = CharToTextEntry(fillwith);
for ( size_t i = start; i <= end; i++ )
vga[i] = entry,
attr[i] = fillattr;
}
bool VGATextBuffer::GetCursorEnabled() const
{
return cursorenabled;
}
void VGATextBuffer::SetCursorEnabled(bool enablecursor)
{
cursorenabled = enablecursor;
UpdateCursor();
}
TextPos VGATextBuffer::GetCursorPos() const
{
return cursorpos;
}
void VGATextBuffer::SetCursorPos(TextPos cursorpos)
{
this->cursorpos = cursorpos;
UpdateCursor();
}
void VGATextBuffer::UpdateCursor()
{
if ( cursorenabled )
VGA::SetCursor(cursorpos.x, cursorpos.y);
else
VGA::SetCursor(width, height-1);
}
} // namespace Sortix