From cdeb045fbd1924d01c1e529975f36f2c8531d777 Mon Sep 17 00:00:00 2001
From: Dirk Best <mail@dirk-best.de>
Date: Wed, 5 Aug 2015 14:37:28 +0200
Subject: [PATCH] screen: add an adjustable global brightness

---
 src/emu/screen.c | 19 ++++++++++++++++++-
 src/emu/screen.h |  5 +++++
 2 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/src/emu/screen.c b/src/emu/screen.c
index 12bf4280dd8..c3bb09e320a 100644
--- a/src/emu/screen.c
+++ b/src/emu/screen.c
@@ -63,6 +63,8 @@ screen_device::screen_device(const machine_config &mconfig, const char *tag, dev
 		m_curtexture(0),
 		m_changed(true),
 		m_last_partial_scan(0),
+		m_color(rgb_t(0xff, 0xff, 0xff, 0xff)),
+		m_brightness(0xff),
 		m_frame_period(DEFAULT_FRAME_PERIOD.as_attoseconds()),
 		m_scantime(1),
 		m_pixeltime(1),
@@ -356,6 +358,7 @@ void screen_device::device_start()
 	save_item(NAME(m_visarea.max_y));
 	save_item(NAME(m_last_partial_scan));
 	save_item(NAME(m_frame_period));
+	save_item(NAME(m_brightness));
 	save_item(NAME(m_scantime));
 	save_item(NAME(m_pixeltime));
 	save_item(NAME(m_vblank_period));
@@ -365,6 +368,17 @@ void screen_device::device_start()
 }
 
 
+//-------------------------------------------------
+//  device_start - device-specific startup
+//-------------------------------------------------
+
+void screen_device::device_reset()
+{
+	// reset brightness to default
+	m_brightness = 0xff;
+}
+
+
 //-------------------------------------------------
 //  device_stop - clean up before the machine goes
 //  away
@@ -884,9 +898,12 @@ bool screen_device::update_quads()
 				m_curbitmap = 1 - m_curbitmap;
 			}
 
+			// brightness adjusted render color
+			rgb_t color = m_color - rgb_t(0, 0xff - m_brightness, 0xff - m_brightness, 0xff - m_brightness);
+
 			// create an empty container with a single quad
 			m_container->empty();
-			m_container->add_quad(0.0f, 0.0f, 1.0f, 1.0f, rgb_t(0xff,0xff,0xff,0xff), m_texture[m_curtexture], PRIMFLAG_BLENDMODE(BLENDMODE_NONE) | PRIMFLAG_SCREENTEX(1));
+			m_container->add_quad(0.0f, 0.0f, 1.0f, 1.0f, color, m_texture[m_curtexture], PRIMFLAG_BLENDMODE(BLENDMODE_NONE) | PRIMFLAG_SCREENTEX(1));
 		}
 	}
 
diff --git a/src/emu/screen.h b/src/emu/screen.h
index 682dd0ce049..29eff3465df 100644
--- a/src/emu/screen.h
+++ b/src/emu/screen.h
@@ -186,10 +186,12 @@ public:
 	render_container &container() const { assert(m_container != NULL); return *m_container; }
 	bitmap_ind8 &priority() { return m_priority; }
 	palette_device *palette() { return m_palette; }
+
 	// dynamic configuration
 	void configure(int width, int height, const rectangle &visarea, attoseconds_t frame_period);
 	void reset_origin(int beamy = 0, int beamx = 0);
 	void set_visible_area(int min_x, int max_x, int min_y, int max_y);
+	void set_brightness(UINT8 brightness) { m_brightness = brightness; }
 
 	// beam positioning and state
 	int vpos() const;
@@ -239,6 +241,7 @@ private:
 	// device-level overrides
 	virtual void device_validity_check(validity_checker &valid) const;
 	virtual void device_start();
+	virtual void device_reset();
 	virtual void device_stop();
 	virtual void device_post_load();
 	virtual void device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr);
@@ -284,6 +287,8 @@ private:
 	INT32               m_last_partial_scan;        // scanline of last partial update
 	bitmap_argb32       m_screen_overlay_bitmap;    // screen overlay bitmap
 	UINT32              m_unique_id;                // unique id for this screen_device
+	rgb_t				m_color;					// render color
+	UINT8				m_brightness;				// global brightness
 
 	// screen timing
 	attoseconds_t       m_frame_period;             // attoseconds per frame