xref: /haiku/src/add-ons/accelerants/intel_extreme/cursor.cpp (revision 1c34b9b1f5e168501f89a270233457e04aa1b16b)

/*
 * Copyright 2006-2008, Haiku, Inc. All Rights Reserved.
 * Distributed under the terms of the MIT License.
 *
 * Authors:
 *		Axel Dörfler, axeld@pinc-software.de
 */


#include "accelerant_protos.h"
#include "accelerant.h"

#include <string.h>


status_t
intel_set_cursor_shape(uint16 width, uint16 height, uint16 hotX, uint16 hotY,
	uint8 *andMask, uint8 *xorMask)
{
	if (width > 64 || height > 64)
		return B_BAD_VALUE;

	write32(INTEL_CURSOR_CONTROL, 0);
		// disable cursor

	// In two-color mode, the data is ordered as follows (always 64 bit per line):
	//	plane 1: line 0 (AND mask)
	//	plane 0: line 0 (XOR mask)
	//	plane 1: line 1 (AND mask)
	//	...
	//
	// If the planes add to the value 0x2, the corresponding pixel is
	// transparent, for 0x3 it inverts the background, so only the first
	// two palette entries will be used (since we're using the 2 color mode).

	uint8 *data = gInfo->shared_info->cursor_memory;
	uint8 byteWidth = (width + 7) / 8;

	for (int32 y = 0; y < height; y++) {
		for (int32 x = 0; x < byteWidth; x++) {
			data[16 * y + x] = andMask[byteWidth * y + x];
			data[16 * y + x + 8] = xorMask[byteWidth * y + x];
		}
	}

	// We can only change the width of the pixel, but apparently
	// not the height (or at least I couldn't figure out how),
	// so we need to make the rest transparent
	for (uint32 y = height; y < 64; y++) {
		for (int32 x = 0; x < byteWidth; x++) {
			data[16 * y + x] = 0xff;
			data[16 * y + x + 8] = 0;
		}
	}

	// set palette entries to white/black
	write32(INTEL_CURSOR_PALETTE + 0, 0x00ffffff);
	write32(INTEL_CURSOR_PALETTE + 4, 0);

	gInfo->shared_info->cursor_format = CURSOR_FORMAT_2_COLORS;

	write32(INTEL_CURSOR_CONTROL, CURSOR_ENABLED | gInfo->shared_info->cursor_format);
	write32(INTEL_CURSOR_SIZE, width);
		// TODO: I've no idea how to specify the height of the cursor - it seems to
		//	be always 64 pixels

	write32(INTEL_CURSOR_BASE, (uint32)gInfo->shared_info->physical_graphics_memory
		+ gInfo->shared_info->cursor_buffer_offset);

	// changing the hot point changes the cursor position, too

	if (hotX != gInfo->shared_info->cursor_hot_x
		|| hotY != gInfo->shared_info->cursor_hot_y) {
		int32 x = read32(INTEL_CURSOR_POSITION);
		int32 y = x >> 16;
		x &= 0xffff;

		if (x & CURSOR_POSITION_NEGATIVE)
			x = -(x & CURSOR_POSITION_MASK);
		if (y & CURSOR_POSITION_NEGATIVE)
			y = -(y & CURSOR_POSITION_MASK);

		x += gInfo->shared_info->cursor_hot_x;
		y += gInfo->shared_info->cursor_hot_y;

		gInfo->shared_info->cursor_hot_x = hotX;
		gInfo->shared_info->cursor_hot_y = hotY;

		intel_move_cursor(x, y);
	}

	return B_OK;
}


void
intel_move_cursor(uint16 _x, uint16 _y)
{
	int32 x = (int32)_x - gInfo->shared_info->cursor_hot_x;
	int32 y = (int32)_y - gInfo->shared_info->cursor_hot_x;

	if (x < 0)
		x = -x | CURSOR_POSITION_NEGATIVE;
	if (y < 0)
		y = -y | CURSOR_POSITION_NEGATIVE;

	write32(INTEL_CURSOR_POSITION, (y << 16) | x);
}


void
intel_show_cursor(bool isVisible)
{
	if (gInfo->shared_info->cursor_visible == isVisible)
		return;

	write32(INTEL_CURSOR_CONTROL, (isVisible ? CURSOR_ENABLED : 0)
		| gInfo->shared_info->cursor_format);
	write32(INTEL_CURSOR_BASE, (uint32)gInfo->shared_info->physical_graphics_memory
		+ gInfo->shared_info->cursor_buffer_offset);

	gInfo->shared_info->cursor_visible = isVisible;
}