#define BRESENHAM_LOOP(color) { \
	if (steep) \
		fb[x * width + y] = color; \
	else \
		fb[y * width + x] = color; \
	\
	while (x != x2) { \
		x += xstep; \
		error += derror; \
		\
		if (error << 1 >= dx) { \
			y += ystep; \
			error -= dx; \
		} \
		\
		if (steep) \
			fb[x * width + y] = color; \
		else \
			fb[y * width + x] = color; \
	} \
}

inline uint32
rgb_to_32(rgb_color color)
{
	return (color.alpha << 24) | (color.red << 16) | (color.green << 8) | (color.blue);
}

void
AccelerantDriver::StrokeSolidLine(int32 x1, int32 y1, int32 x2, int32 y2, const RGBColor &_color)
{
	RGBColor color = _color;
	int32 width = mFrameBufferConfig.bytes_per_row;
	
	// setup variables for bresenham algorithm
	bool steep = abs(y2 - y1) > abs(x2 - x1);
	if (steep) {
		// swap x1 and y1
		int32 temp = x1;
		x1 = y1;
		y1 = temp;
		
		// swap x2 and y2
		temp = x2;
		x2 = y2;
		y2 = temp;
	}
	
	int32 dx = abs(x2 - x1);
	int32 dy = abs(y2 - y1);
	int32 error = 0;
	int32 derror = dy;
	int32 x = x1;
	int32 y = y1;
	int32 xstep = 1;
	int32 ystep = 1;
	
	if (x1 >= x2)
		xstep = -1;
	if (y1 >= y2)
		ystep = -1;
	
	switch (mDisplayMode.space)
	{
		case B_CMAP8:
		case B_GRAY8:
			{
				uint8 *fb = (uint8 *)mFrameBufferConfig.frame_buffer;
				uint8 draw_color = color.GetColor8();
				BRESENHAM_LOOP(draw_color);
			} break;
		case B_RGB15_BIG:
		case B_RGBA15_BIG:
		case B_RGB15_LITTLE:
		case B_RGBA15_LITTLE:
			{
				uint16 *fb = (uint16 *)mFrameBufferConfig.frame_buffer;
				uint16 draw_color = color.GetColor15();
				width /= 2;
				BRESENHAM_LOOP(draw_color);
			} break;
		case B_RGB16_BIG:
		case B_RGB16_LITTLE:
			{
				uint16 *fb = (uint16 *)mFrameBufferConfig.frame_buffer;
				uint16 draw_color = color.GetColor16();
				width /= 2;
				BRESENHAM_LOOP(draw_color);
			} break;
		case B_RGB32_BIG:
		case B_RGBA32_BIG:
		case B_RGB32_LITTLE:
		case B_RGBA32_LITTLE:
			{
				uint32 *fb = (uint32 *)mFrameBufferConfig.frame_buffer;
				uint32 draw_color = rgb_to_32(color.GetColor32());
				width /= 4;
				BRESENHAM_LOOP(draw_color);
			} break;
		default:
			printf("Error: Unknown color space\n");
	}
}

void AccelerantDriver::StrokePatternLine(int32 x1, int32 y1, int32 x2, int32 y2, const DrawData *d)
{
	PatternHandler drawPattern(d->patt);
	int32 width = mFrameBufferConfig.bytes_per_row;
	
	// setup variables for bresenham algorithm
	bool steep = abs(y2 - y1) > abs(x2 - x1);
	if (steep) {
		// swap x1 and y1
		int32 temp = x1;
		x1 = y1;
		y1 = temp;
		
		// swap x2 and y2
		temp = x2;
		x2 = y2;
		y2 = temp;
	}
	
	int32 dx = abs(x2 - x1);
	int32 dy = abs(y2 - y1);
	int32 error = 0;
	int32 derror = dy;
	int32 x = x1;
	int32 y = y1;
	int32 xstep = 1;
	int32 ystep = 1;
	
	if (x1 >= x2)
		xstep = -1;
	if (y1 >= y2)
		ystep = -1;
	
	switch (mDisplayMode.space)
	{
		case B_CMAP8:
		case B_GRAY8:
			{
				uint8 *fb = (uint8 *)mFrameBufferConfig.frame_buffer;
				BRESENHAM_LOOP(drawPattern.ColorAt((float)x,(float)y).GetColor8());
			} break;
		case B_RGB15_BIG:
		case B_RGBA15_BIG:
		case B_RGB15_LITTLE:
		case B_RGBA15_LITTLE:
			{
				uint16 *fb = (uint16 *)mFrameBufferConfig.frame_buffer;
				width /= 2;
				BRESENHAM_LOOP(drawPattern.ColorAt((float)x,(float)y).GetColor15());
			} break;
		case B_RGB16_BIG:
		case B_RGB16_LITTLE:
			{
				uint16 *fb = (uint16 *)mFrameBufferConfig.frame_buffer;
				width /= 2;
				BRESENHAM_LOOP(drawPattern.ColorAt((float)x,(float)y).GetColor16());
			} break;
		case B_RGB32_BIG:
		case B_RGBA32_BIG:
		case B_RGB32_LITTLE:
		case B_RGBA32_LITTLE:
			{
				uint32 *fb = (uint32 *)mFrameBufferConfig.frame_buffer;
				width /= 4;
				BRESENHAM_LOOP(rgb_to_32(drawPattern.ColorAt((float)x,(float)y).GetColor32()));
			} break;
		default:
			printf("Error: Unknown color space\n");
	}
}