usgames.cpp: converted to 6845 update row, fixes screen alignment [Angelo Salese]

src/mame/drivers/usgames.cpp

@@ -77,7 +77,7 @@ void usgames_state::usgames_map(address_map &map)
 	map(0x2070, 0x2070).portr("UNK2");
 	map(0x2400, 0x2401).w("aysnd", FUNC(ay8912_device::address_data_w));
 	map(0x2800, 0x2fff).ram().w(FUNC(usgames_state::charram_w)).share("charram");
-	map(0x3000, 0x3fff).ram().w(FUNC(usgames_state::videoram_w)).share("videoram");
+	map(0x3000, 0x3fff).ram().share("videoram");
 	map(0x4000, 0x7fff).bankr("bank1");
 	map(0x8000, 0xffff).rom();
 }
@@ -97,7 +97,7 @@ void usgames_state::usg185_map(address_map &map)
 	map(0x2460, 0x2460).w(FUNC(usgames_state::rombank_w));
 	map(0x2470, 0x2470).portr("UNK2");
 	map(0x2800, 0x2fff).ram().w(FUNC(usgames_state::charram_w)).share("charram");
-	map(0x3000, 0x3fff).ram().w(FUNC(usgames_state::videoram_w)).share("videoram");
+	map(0x3000, 0x3fff).ram().share("videoram");
 	map(0x4000, 0x7fff).bankr("bank1");
 	map(0x8000, 0xffff).rom();
 }
@@ -214,7 +214,7 @@ static const gfx_layout charlayout =
 };
 
 static GFXDECODE_START( gfx_usgames )
-	GFXDECODE_ENTRY( nullptr, 0x2800, charlayout, 0, 256 )
+	GFXDECODE_ENTRY( nullptr, 0x2800, charlayout, 0, 1 )
 GFXDECODE_END
 
 
@@ -233,15 +233,16 @@ void usgames_state::usg32(machine_config &config)
 	screen.set_vblank_time(ATTOSECONDS_IN_USEC(2500) /* not accurate */);
 	screen.set_size(64*8, 32*8);
 	screen.set_visarea(7*8, 57*8-1, 0*8, 31*8-1);
-	screen.set_screen_update(FUNC(usgames_state::screen_update));
+	screen.set_screen_update("crtc", FUNC(mc6845_device::screen_update));
 
 	GFXDECODE(config, m_gfxdecode, "palette", gfx_usgames);
-	PALETTE(config, "palette", FUNC(usgames_state::usgames_palette), 2*256);
+	PALETTE(config, "palette", FUNC(usgames_state::usgames_palette), 16);
 
 	mc6845_device &crtc(MC6845(config, "crtc", 18_MHz_XTAL / 16));
 	crtc.set_screen("screen");
 	crtc.set_show_border_area(false);
 	crtc.set_char_width(8);
+	crtc.set_update_row_callback(FUNC(usgames_state::update_row), this);
 
 	/* sound hardware */
 	SPEAKER(config, "mono").front_center();

src/mame/includes/usgames.h

@@ -6,6 +6,7 @@
 #pragma once
 
 #include "emupal.h"
+#include "video/mc6845.h"
 
 class usgames_state : public driver_device
 {
@@ -16,7 +17,8 @@ public:
 		m_gfxdecode(*this, "gfxdecode"),
 		m_videoram(*this, "videoram"),
 		m_charram(*this, "charram"),
-		m_leds(*this, "led%u", 0U)
+		m_leds(*this, "led%u", 0U),
+		m_palette(*this, "palette")
 	{ }
 
 	void usg32(machine_config &config);
@@ -34,22 +36,18 @@ private:
 	required_shared_ptr<uint8_t> m_charram;
 
 	output_finder<5> m_leds;
-
+	required_device<palette_device> m_palette;
-	tilemap_t *m_tilemap;
 
 	DECLARE_WRITE8_MEMBER(rombank_w);
 	DECLARE_WRITE8_MEMBER(lamps1_w);
 	DECLARE_WRITE8_MEMBER(lamps2_w);
-	DECLARE_WRITE8_MEMBER(videoram_w);
 	DECLARE_WRITE8_MEMBER(charram_w);
 
-	TILE_GET_INFO_MEMBER(get_tile_info);
-
 	void usgames_palette(palette_device &palette) const;
 
-	uint32_t screen_update(screen_device &screen, bitmap_rgb32 &bitmap, const rectangle &cliprect);
 	void usg185_map(address_map &map);
 	void usgames_map(address_map &map);
+	MC6845_UPDATE_ROW(update_row);
 };
 
 #endif // MAME_INCLUDES_USGAMES_H

src/mame/video/usgames.cpp

@@ -6,14 +6,12 @@
 
 void usgames_state::usgames_palette(palette_device &palette) const
 {
-	for (int j = 0; j < 0x200; j++)
+	for (int j = 0; j < 16; j++)
 	{
-		int const data = (j >> ((j & 0x01) ? 5 : 1)) & 0x0f;
+		int r = BIT(j, 0);
-
+		int g = BIT(j, 1);
-		int r = BIT(data, 0);
+		int b = BIT(j, 2);
-		int g = BIT(data, 1);
+		int const i = BIT(j, 3);
-		int b = BIT(data, 2);
-		int const i = BIT(data, 3);
 
 		r = 0xff * r;
 		g = 0x7f * g * (i + 1);
@@ -23,38 +21,33 @@ void usgames_state::usgames_palette(palette_device &palette) const
 	}
 }
 
-
-
-TILE_GET_INFO_MEMBER(usgames_state::get_tile_info)
-{
-	int const tileno = m_videoram[tile_index*2];
-	int const colour = m_videoram[tile_index*2+1];
-
-	SET_TILE_INFO_MEMBER(0, tileno, colour, 0);
-}
-
 void usgames_state::video_start()
 {
-	m_tilemap = &machine().tilemap().create(*m_gfxdecode, tilemap_get_info_delegate(FUNC(usgames_state::get_tile_info),this),TILEMAP_SCAN_ROWS, 8, 8,64,32);
 	m_gfxdecode->gfx(0)->set_source(m_charram);
 }
 
-
-WRITE8_MEMBER(usgames_state::videoram_w)
-{
-	m_videoram[offset] = data;
-	m_tilemap->mark_tile_dirty(offset/2);
-}
-
 WRITE8_MEMBER(usgames_state::charram_w)
 {
 	m_charram[offset] = data;
 	m_gfxdecode->gfx(0)->mark_dirty(offset/8);
 }
 
-
+MC6845_UPDATE_ROW(usgames_state::update_row)
-uint32_t usgames_state::screen_update(screen_device &screen, bitmap_rgb32 &bitmap, const rectangle &cliprect)
 {
-	m_tilemap->draw(screen, bitmap, cliprect, 0,0);
+	uint32_t *pix = &bitmap.pix32(y);
-	return 0;
+	ra &= 0x07;
+
+	for (int x = 0; x < x_count; x++)
+	{
+		int tile_index = (x + ma) & (m_videoram.mask()/2);
+		int tile = m_videoram[tile_index*2];
+		int attr = m_videoram[tile_index*2+1];
+		uint8_t bg_color = attr & 0xf;
+		uint8_t fg_color = (attr & 0xf0) >> 4;
+		
+		const uint8_t plane = m_charram[(tile << 3) | ra];
+		for (int n = 7; n >= 0; n--)
+			*pix++ = m_palette->pen(BIT(plane, n) ? fg_color : bg_color);
+	}
 }
+