Replacement to system("color") - c++

Question

I need a method that acts like system color without using a system call. I know there is setConsoleTextAttribute() but that doesn't fill the full foreground and background with color only new characters. I am using windows7 although i would like to make this compatible with all windows

Answer 1

As per your comments, here is a more complete solution to the problem you are trying to solve. It is based on my original answer (which can be found at the end of this answer).
I discovered one limitation in Windows API, namely that it cannot read the entire screen buffer for a default console mode window of 80 columns by 300 rows. It results in a ERROR_NOT_ENOUGH_MEMORY error due to insufficient Windows process heap (as best as I can tell from some Google searching). I wound up implementing a wrapper around the XxxConsoleOutput functions to support automatic subdivision of the screen buffer region as needed until the function succeeds or it fails to read a 1 X 1 (single character) region.
Again, this code is probably not perfect, it is meant to explain concepts, not to (necessarily) provide you with a complete solution. However, it now fills the entire console (previously I only filled the visible portion of the window) and sets the console's text attribute for future output.
Skip this code to read the original answer.
#define WIN32_LEAN_AND_MEAN
#include <Windows.h>
#include <iostream>
#include <vector>
using namespace std;
// Split a rectangular region into two smaller rectangles
// based on the largest dimension.
void SplitRegion(
SHORT width, SHORT height,
COORD dwBufferCoord, const SMALL_RECT& readRegion,
COORD& dwBufferCoordA, SMALL_RECT& readRegionA,
COORD& dwBufferCoordB, SMALL_RECT& readRegionB)
{
dwBufferCoordA = dwBufferCoordB = dwBufferCoord;
readRegionA = readRegionB = readRegion;
if (height >= width)
{
SHORT half = height / 2;
dwBufferCoordB.Y += half;
readRegionB.Top += half;
readRegionA.Bottom = readRegionB.Top - 1;
}
else
{
SHORT half = width / 2;
dwBufferCoordB.X += half;
readRegionB.Left += half;
readRegionA.Right = readRegionB.Left - 1;
}
}
// Utility function to figure out the distance
// between two points.
template <typename type>
inline type DiffHelper(type first, type second)
{
return (second >= first) ? (second - first + 1) : 0;
}
// A template that wraps up the shared code common between
// reading and writing the screen buffer. If it is ever
// given a region of zero width or height, it will
// "succeed". If it ever tries to subdivide a 1 by 1
// region, it will fail.
template <typename lpBufferType>
BOOL XferConsoleOutputWrapper(
HANDLE hConsoleOutput,
lpBufferType lpBuffer,
COORD dwBufferSize,
COORD dwBufferCoord,
SMALL_RECT& xferRegion,
BOOL (WINAPI * xferConsoleOutput)(
HANDLE, lpBufferType, COORD, COORD, PSMALL_RECT))
{
SHORT width = DiffHelper(xferRegion.Left, xferRegion.Right);
SHORT height = DiffHelper(xferRegion.Top, xferRegion.Bottom);
if ((width == 0) || (height == 0))
{
return TRUE;
}
BOOL success = xferConsoleOutput(hConsoleOutput,
lpBuffer, dwBufferSize, dwBufferCoord, &xferRegion);
if (!success)
{
if ((GetLastError() == ERROR_NOT_ENOUGH_MEMORY) &&
((width * height) > 1))
{
COORD dwBufferCoordA, dwBufferCoordB;
SMALL_RECT xferRegionA, xferRegionB;
SplitRegion(
width, height,
dwBufferCoord, xferRegion,
dwBufferCoordA, xferRegionA,
dwBufferCoordB, xferRegionB);
success =
XferConsoleOutputWrapper(hConsoleOutput, lpBuffer, dwBufferSize,
dwBufferCoordA, xferRegionA, xferConsoleOutput) &&
XferConsoleOutputWrapper(hConsoleOutput, lpBuffer, dwBufferSize,
dwBufferCoordB, xferRegionB, xferConsoleOutput);
}
}
return success;
}
// ReadConsoleOutput failed to read an 80 by 300 character screen
// buffer in a single call, resulting in ERROR_NOT_ENOUGH_MEMORY.
// ReadConsoleOutputWrapper will subdivide the operation into
// smaller and smaller chunks as needed until it succeeds in reading
// the entire screen buffer.
inline BOOL ReadConsoleOutputWrapper(
HANDLE hConsoleOutput,
PCHAR_INFO lpBuffer,
COORD dwBufferSize,
COORD dwBufferCoord,
SMALL_RECT& readRegion)
{
return XferConsoleOutputWrapper(hConsoleOutput, lpBuffer, dwBufferSize,
dwBufferCoord, readRegion, ReadConsoleOutput);
}
// WriteConsoleOutputWrapper will subdivide the operation into
// smaller and smaller chunks as needed until it succeeds in writing
// the entire screen buffer. This may not be necessary as
// WriteConsoleOutput never failed, but it was simple to implement
// so it was done just to be safe.
inline BOOL WriteConsoleOutputWrapper(
HANDLE hConsoleOutput,
const CHAR_INFO* lpBuffer,
COORD dwBufferSize,
COORD dwBufferCoord,
SMALL_RECT& writeRegion)
{
return XferConsoleOutputWrapper(hConsoleOutput, lpBuffer, dwBufferSize,
dwBufferCoord, writeRegion, WriteConsoleOutput);
}
void ConsoleFillWithAttribute(WORD fillAttribute)
{
// Get the handle to the output
HANDLE hStdout = GetStdHandle(STD_OUTPUT_HANDLE);
// Get the information for the current screen buffer
CONSOLE_SCREEN_BUFFER_INFO info;
GetConsoleScreenBufferInfo(hStdout, &info);
// Allocate a vector to hold the visible screen buffer data
vector<CHAR_INFO> buffer(info.dwSize.X * info.dwSize.Y);
// Initialize a couple of pointers to the begin and end of the buffer
CHAR_INFO* begin = buffer.data();
CHAR_INFO* end = begin + buffer.size();
// Start at the upper left corner of the screen buffer.
COORD coord;
coord.X = coord.Y = 0;
// Initialize the region to encompass the entire screen buffer.
SMALL_RECT region;
region.Left = region.Top = 0;
region.Right = info.dwSize.X - 1;
region.Bottom = info.dwSize.Y - 1;
// Read the buffer from the console into the CHAR_INFO vector.
ReadConsoleOutputWrapper(hStdout, buffer.data(), info.dwSize, coord, region);
// Change all the attributes to the specified fill attribute.
while (begin != end)
{
begin->Attributes = fillAttribute;
++begin;
}
// Write the buffer from the CHAR_INFO vector back to the console.
WriteConsoleOutputWrapper(hStdout, buffer.data(), info.dwSize, coord, region);
// Finally, set the console text attribute to the fill attribute
// so that all new text will be printed in the same manner as
// the attributes we just changed.
SetConsoleTextAttribute(hStdout, fillAttribute);
}
int main()
{
cout << "I would like to fill up the console with some text." << endl;
cout << "The quick brown fox jumped over the lazy dogs." << endl;
for (int i = 0; i < 100; ++i)
{
cout << ' ' << i;
}
cout << endl;
ConsoleFillWithAttribute(
BACKGROUND_BLUE | FOREGROUND_INTENSITY |
FOREGROUND_RED | FOREGROUND_GREEN);
cout << endl;
cout << "This should also be printed in the new attribute" << endl;
return 0;
}
The original answer is below:
If I understand what you are asking, you want to be able to change the attributes for the entire console mode window. You might want to look into the ReadConsoleOutput and WriteConsoleOutput functions. You can use ReadConsoleOutput to read some or all of a console buffer into memory, then manipulate the attribute data as needed for your application, then use WriteConsoleOutput to write memory back to the console output buffer.
Here is some code that will change the attributes for the currently displayed portion of console (assuming output has not been redirected to a non-console handle):
#define WIN32_LEAN_AND_MEAN
#include <Windows.h>
#include <iostream>
#include <vector>
using namespace std;
void ConsoleFillDisplayWithAttribute(WORD fillAttribute)
{
// Get the handle to the output
HANDLE hStdout = GetStdHandle(STD_OUTPUT_HANDLE);
// Get the information for the current screen buffer
CONSOLE_SCREEN_BUFFER_INFO info;
GetConsoleScreenBufferInfo(hStdout, &info);
// Calculate the size of the displayed portion of the screen buffer
COORD size;
size.X = (info.srWindow.Right - info.srWindow.Left + 1);
size.Y = (info.srWindow.Bottom - info.srWindow.Top + 1);
// Allocate a vector to hold the visible screen buffer data
vector<CHAR_INFO> buffer(size.X * size.Y);
COORD coord;
coord.X = coord.Y = 0;
// Read the buffer from the console into the CHAR_INFO vector
ReadConsoleOutput(hStdout, buffer.data(), size, coord, &info.srWindow);
// Initialize a couple of pointers to the begin and end of the buffer
CHAR_INFO* begin = buffer.data();
CHAR_INFO* end = begin + buffer.size();
// Change all the attributes to the specified fill attribute
while (begin != end)
{
begin->Attributes = fillAttribute;
++begin;
}
// Write the buffer from the CHAR_INFO vector back to the console
WriteConsoleOutput(hStdout, buffer.data(), size, coord, &info.srWindow);
}
int main()
{
cout << "I would like to fill up the console with some text." << endl;
cout << "The quick brown fox jumped over the lazy dogs." << endl;
for (int i = 0; i < 100; ++i)
{
cout << ' ' << i;
}
cout << endl;
ConsoleFillDisplayWithAttribute(
BACKGROUND_BLUE | FOREGROUND_INTENSITY |
FOREGROUND_RED | FOREGROUND_GREEN);
return 0;
}