blob: 60ba1928bdc33071ba35548288143a6de266ac11 (
plain) (
tree)
|
|
// license:BSD-3-Clause
// copyright-holders:Nathan Woods
/***************************************************************************
video/advision.c
Routines to control the Adventurevision video hardware
Video hardware is composed of a vertical array of 40 LEDs which is
reflected off a spinning mirror, to give a resolution of 150 x 40 at 15 FPS.
***************************************************************************/
#include "emu.h"
#include "includes/advision.h"
#include <algorithm>
/***************************************************************************
Start the video hardware emulation.
***************************************************************************/
void advision_state::video_start()
{
m_video_hpos = 0;
m_display = std::make_unique<uint8_t []>(8 * 8 * 256);
std::fill_n(m_display.get(), 8 * 8 * 256, 0);
save_pointer(NAME(m_display), 8 * 8 * 256);
save_item(NAME(m_video_hpos));
}
/***************************************************************************
Initialise the palette.
***************************************************************************/
void advision_state::advision_palette(palette_device &palette) const
{
// 8 shades of RED
for (int i = 0; i < 8; i++)
m_palette->set_pen_color(i, pal3bit(i), 0x00, 0x00);
}
/***************************************************************************
Update the display data.
***************************************************************************/
void advision_state::vh_write(int data)
{
if (m_video_bank >= 1 && m_video_bank <=5)
m_led_latch[m_video_bank] = data;
}
void advision_state::vh_update(int x)
{
uint8_t *dst = &m_display[x];
for (int y = 0; y < 8; y++)
{
uint8_t data = m_led_latch[7 - y];
for (int i = 0; i < 8; i++)
{
if (!BIT(data, 7 - i))
dst[i * 256] = 8;
}
m_led_latch[7 - y] = 0xff;
dst += 8 * 256;
}
}
/***************************************************************************
Refresh the video screen
***************************************************************************/
uint32_t advision_state::screen_update(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect)
{
if ((m_frame_count++ % 4) == 0)
{
m_frame_start = 1;
m_video_hpos = 0;
}
for (int x = 0; x < 150; x++)
{
uint8_t *led = &m_display[x];
for (int y = 0; y < 128; y+=2)
{
if (*led > 0)
bitmap.pix16(30 + y, 85 + x) = --(*led);
else
bitmap.pix16(30 + y, 85 + x) = 0;
led += 256;
}
}
return 0;
}
|