Last day I made a quick hack to draw text and lines with DirectDraw as I have started to work on a new game. I use the GDI function, I think it is DrawLine or something. It works for a while, but then it doesn't work to draw lines anymore. The whole thing starts when I'm moving the mouse or pressing any keys for a while. It seams to be something with the messageloop but I can't track it. I'm using the function every frame, because I erase the backbuffer every frame. I'm drawing text with TextOut the same way, but that works perfect. What am I doing wrong???????? Edited by - Digger on 2/1/00 7:58:30 AM

It''s hard to tell without actually looking at the code, but here''s a couple of possible problems that can crop up using GDI:

- You''re creating a compatible device context but never deleting it
- You''re creating an HBRUSH, HBITMAP, HICON, or something similar in your drawing function but never deselecting and deleting it

-fel

//***********************//** Normal line://***********************void Prim::Line(int x0, int y0, int x1, int y1){	// Theory: add Dy / Dx to y after every loop	double dy = y1 - y0;	double dx = x1 - x0;	double m;	if(dy < dx)	{		m = dy / dx;		double y = y0;		for(int x = x0; x <= x1; x++)		{			Dest[(int)(((int)y * Pitch) + (x*3))] = (unsigned char) 255;			y += m;		}	}	else	{		double x = x0;		m = dx / dy;		for(int y = y0; y <= y1; y++)		{			Dest[(int)((y * Pitch) + ((int)x * 3))] = (unsigned char) 255;			x += m;		}	}}//*********************//** End normal line//*********************//*********************//** Midpoint algorithm//*********************void Prim::MidPointLine(int x0, int y0, int x1, int y1){	int x, y;	int dx = x1 - x0;	if(dx > 0)	{		x = x0;	}	else	{		dx = -dx;		x = x0;	}	int dy = y1 - y0;	//int x = x0;	y = y0;	int d, IncrE, IncrNE;	Dest[(y * Pitch) + (x*3)] = 255;	if(dy < dx)	{		d =  2 * dy - dx;	    IncrE = 2 * dy;	    IncrNE = 2 * (dy - dx);			while(x < x1)		{			if(d <= 0)			{				d+= IncrE;				x++;			}			else			{				d+=IncrNE;				x++;				y++;			}			Dest[(y * Pitch) + (x*3)] = 255;		}			}	else	{		d =  2 * dx - dy;	    IncrE = 2 * dx;	    IncrNE = 2 * (dx - dy);			while(y < y1)		{			if(d <= 0)			{				d+= IncrE;				y++;			}			else			{				d+=IncrNE;				x++;				y++;			}			Dest[(y * Pitch) + (x*3)] = 255;		}	}}//***********************//** End Midpoint algorithme//***********************//***********************//** Bresenham''s algorithme//***********************void Prim::BressenhamLine(int x0, int y0, int x1, int y1){	int XUnit, YUnit, Offset = y0 * Pitch + (x0*3);	int dy = y1 - y0;	if(dy < 0)	{		dy = -dy;		YUnit = -Pitch;	}	else		YUnit = Pitch;	int dx = x1 - x0;	if(dx < 0)	{		dx = -dx;		XUnit = -3;	}	else XUnit = 3;	int ErrorTerm = 0;	if(dx > dy)	{		for(int i = 0; i <= dx; i++)		{			Dest[Offset] = 255;			Dest[Offset+1] = 0;			Dest[Offset+2] = 0;			Offset += XUnit;			ErrorTerm += dy;			while(ErrorTerm > dx)			{				ErrorTerm -= dx;				Offset += YUnit;			}		}	}	else	{		for(int i = 0; i <= dy; i++)		{			Dest[Offset] = 255;			Dest[Offset+1] = 0;			Dest[Offset+2] = 0;			Offset += YUnit;			ErrorTerm += dx;			while(ErrorTerm > 0)			{				ErrorTerm -= dy;				Offset += XUnit;			}		}	}}//************************//** End Bresenham''s algorithm//************************[/CODE}I know it''s bressenhma, but wrote this code some time ago, and can''t seem to find the time to change it with some enhancements I came up with......    

Dance with me......

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