amiga/amigaaga.cpp: implement palette reads

mamedev · Feb 4, 2025 · f92cb92 · f92cb92
1 parent a7b26f0
commit f92cb92
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Showing 3 changed files with 38 additions and 23 deletions.
diff --git a/src/mame/amiga/amiga.h b/src/mame/amiga/amiga.h
@@ -660,7 +660,8 @@ class amiga_state : public driver_device
 	void render_scanline(bitmap_rgb32 &bitmap, int scanline);
 
 	// AGA video helpers
-	void aga_palette_write(int color_reg, uint16_t data);
+	u16 aga_palette_read(offs_t color_reg);
+	void aga_palette_write(offs_t color_reg, uint16_t data);
 	void aga_fetch_sprite_data(int scanline, int sprite);
 	void aga_render_scanline(bitmap_rgb32 &bitmap, int scanline);
 	void aga_update_sprite_dma(int scanline, int num);

diff --git a/src/mame/amiga/amiga_m.cpp b/src/mame/amiga/amiga_m.cpp
@@ -1191,7 +1191,17 @@ void amiga_state::ocs_map(address_map &map)
 	// Sprite section
 //  map(0x120, 0x17f).m(amiga_state::sprxpt_map));
 	// Color section
-//  map(0x180, 0x1bf).m(amiga_state::colorxx_map));
+	map(0x180, 0x1bf).lrw16(
+		NAME([this] (offs_t offset) {
+			return CUSTOM_REG(REG_COLOR00 + offset);
+		}),
+		NAME([this] (offs_t offset, u16 data) {
+			CUSTOM_REG(REG_COLOR00 + offset) = data;
+			data &= 0xfff;
+			// Extra Half-Brite
+			CUSTOM_REG(REG_COLOR00 + offset + 32) = (data >> 1) & 0x777;
+		})
+	);
 }
 
 void amiga_state::ecs_map(address_map &map)
@@ -1229,6 +1239,8 @@ void amiga_state::aga_map(address_map &map)
 
 	map(0x10e, 0x10f).w(FUNC(amiga_state::clxcon2_w));
 
+	map(0x180, 0x1bf).rw(FUNC(amiga_state::aga_palette_read), FUNC(amiga_state::aga_palette_write));
+
 	// UHRES regs
 	// TODO: may be shared with ECS?
 //  map(0x1e6, 0x1e7).w(FUNC(amiga_state::bplhmod_w));
@@ -1699,26 +1711,6 @@ void amiga_state::custom_chip_w(offs_t offset, uint16_t data)
 			data &= ~1;
 			break;
 
-		case REG_COLOR00:   case REG_COLOR01:   case REG_COLOR02:   case REG_COLOR03:
-		case REG_COLOR04:   case REG_COLOR05:   case REG_COLOR06:   case REG_COLOR07:
-		case REG_COLOR08:   case REG_COLOR09:   case REG_COLOR10:   case REG_COLOR11:
-		case REG_COLOR12:   case REG_COLOR13:   case REG_COLOR14:   case REG_COLOR15:
-		case REG_COLOR16:   case REG_COLOR17:   case REG_COLOR18:   case REG_COLOR19:
-		case REG_COLOR20:   case REG_COLOR21:   case REG_COLOR22:   case REG_COLOR23:
-		case REG_COLOR24:   case REG_COLOR25:   case REG_COLOR26:   case REG_COLOR27:
-		case REG_COLOR28:   case REG_COLOR29:   case REG_COLOR30:   case REG_COLOR31:
-			if (IS_AGA())
-			{
-				aga_palette_write(offset - REG_COLOR00, data);
-			}
-			else
-			{
-				data &= 0xfff;
-				// Extra Half-Brite
-				CUSTOM_REG(offset + 32) = (data >> 1) & 0x777;
-			}
-			break;
-
 		// display window start/stop
 		case REG_DIWSTRT:
 		case REG_DIWSTOP:

diff --git a/src/mame/amiga/amigaaga.cpp b/src/mame/amiga/amigaaga.cpp
@@ -41,7 +41,26 @@
  *
  *************************************/
 
-void amiga_state::aga_palette_write(int color_reg, uint16_t data)
+u16 amiga_state::aga_palette_read(offs_t color_reg)
+{
+	u8 pal_bank = (CUSTOM_REG(REG_BPLCON3) >> 13) & 0x07;
+
+	int color = (pal_bank * 32) + color_reg;
+
+	u8 cr = m_aga_palette[color].r();
+	u8 cg = m_aga_palette[color].g();
+	u8 cb = m_aga_palette[color].b();
+
+	// LOCT
+	if (BIT(CUSTOM_REG(REG_BPLCON3),9))
+	{
+		return ((cr & 0xf) << 8) | ((cg & 0xf) << 4) | ((cb & 0xf) << 0);
+	}
+
+	return ((cr & 0xf0) << 4) | (cg & 0xf0) | ((cb & 0xf0) >> 4);
+}
+
+void amiga_state::aga_palette_write(offs_t color_reg, uint16_t data)
 {
 	int r,g,b;
 	int cr,cg,cb;
@@ -68,7 +87,9 @@ void amiga_state::aga_palette_write(int color_reg, uint16_t data)
 		cr = (r << 4) | r;
 		cg = (g << 4) | g;
 		cb = (b << 4) | b;
+		// TODO: transparency, bit 15
 	}
+
 	m_aga_palette[color] = rgb_t(cr, cg, cb);
 	// make a copy for Extra Half Brite mode
 	if (pal_bank == 0)
@@ -499,6 +520,7 @@ void amiga_state::aga_render_scanline(bitmap_rgb32 &bitmap, int scanline)
 			CUSTOM_REG(REG_VPOSR) ^= VPOSR_LOF;
 
 		m_copper->vblank_sync(true);
+		// TODO: shouldn't be raw color ...
 		m_ham_color = CUSTOM_REG(REG_COLOR00);
 	}