Fix various Automap drawing issues (#6555)

Source/automap.h

@@ -36,11 +36,55 @@ extern uint8_t AutomapView[DMAXX][DMAXY];
 extern DVL_API_FOR_TEST int AutoMapScale;
 extern DVL_API_FOR_TEST Displacement AutomapOffset;
 
-inline int AmLine(int x)
+/** Defines the offsets used for Automap lines */
+enum class AmWidthOffset : int8_t {
+	None,
+	EighthTileRight = TILE_WIDTH >> 4,
+	QuarterTileRight = TILE_WIDTH >> 3,
+	HalfTileRight = TILE_WIDTH >> 2,
+	ThreeQuartersTileRight = (TILE_WIDTH >> 1) - (TILE_WIDTH >> 3),
+	FullTileRight = TILE_WIDTH >> 1,
+	DoubleTileRight = TILE_WIDTH,
+	EighthTileLeft = -EighthTileRight,
+	QuarterTileLeft = -QuarterTileRight,
+	HalfTileLeft = -HalfTileRight,
+	ThreeQuartersTileLeft = -ThreeQuartersTileRight,
+	FullTileLeft = -FullTileRight,
+	DoubleTileLeft = -DoubleTileRight,
+};
+
+enum class AmHeightOffset : int8_t {
+	None,
+	EighthTileDown = TILE_HEIGHT >> 4,
+	QuarterTileDown = TILE_HEIGHT >> 3,
+	HalfTileDown = TILE_HEIGHT >> 2,
+	ThreeQuartersTileDown = (TILE_HEIGHT >> 1) - (TILE_HEIGHT >> 3),
+	FullTileDown = TILE_HEIGHT >> 1,
+	DoubleTileDown = TILE_HEIGHT,
+	EighthTileUp = -EighthTileDown,
+	QuarterTileUp = -QuarterTileDown,
+	HalfTileUp = -HalfTileDown,
+	ThreeQuartersTileUp = -ThreeQuartersTileDown,
+	FullTileUp = -FullTileDown,
+	DoubleTileUp = -DoubleTileDown,
+};
+
+enum class AmLineLength : uint8_t {
+	QuarterTile = 2,
+	HalfTile = 4,
+	FullTile = 8,
+	FullAndHalfTile = 12,
+	DoubleTile = 16,
+};
+
+inline Displacement AmOffset(AmWidthOffset x, AmHeightOffset y)
+{
+	return { AutoMapScale * static_cast<int>(x) / 100, AutoMapScale * static_cast<int>(y) / 100 };
+}
+
+inline int AmLine(AmLineLength l)
 {
-	assert(x >= 4 && x <= 64);
-	assert((x & (x - 1)) == 0);
-	return AutoMapScale * x / 100;
+	return AutoMapScale * static_cast<int>(l) / 100;
 }
 
 /**

test/automap_test.cpp

@@ -9,11 +9,11 @@ TEST(Automap, InitAutomap)
 	InitAutomapOnce();
 	EXPECT_EQ(AutomapActive, false);
 	EXPECT_EQ(AutoMapScale, 50);
-	EXPECT_EQ(AmLine(64), 32);
-	EXPECT_EQ(AmLine(32), 16);
-	EXPECT_EQ(AmLine(16), 8);
-	EXPECT_EQ(AmLine(8), 4);
-	EXPECT_EQ(AmLine(4), 2);
+	EXPECT_EQ(AmLine(AmLineLength::DoubleTile), static_cast<int>(AmLineLength::FullTile));
+	EXPECT_EQ(AmLine(AmLineLength::FullAndHalfTile), 6);
+	EXPECT_EQ(AmLine(AmLineLength::FullTile), static_cast<int>(AmLineLength::HalfTile));
+	EXPECT_EQ(AmLine(AmLineLength::HalfTile), static_cast<int>(AmLineLength::QuarterTile));
+	EXPECT_EQ(AmLine(AmLineLength::QuarterTile), 1);
 }
 
 TEST(Automap, StartAutomap)
@@ -65,24 +65,23 @@ TEST(Automap, AutomapZoomIn)
 	AutoMapScale = 50;
 	AutomapZoomIn();
 	EXPECT_EQ(AutoMapScale, 75);
-	EXPECT_EQ(AmLine(64), 48);
-	EXPECT_EQ(AmLine(32), 24);
-	EXPECT_EQ(AmLine(16), 12);
-	EXPECT_EQ(AmLine(8), 6);
-	EXPECT_EQ(AmLine(4), 3);
+	EXPECT_EQ(AmLine(AmLineLength::DoubleTile), static_cast<int>(AmLineLength::FullAndHalfTile));
+	EXPECT_EQ(AmLine(AmLineLength::FullTile), 6);
+	EXPECT_EQ(AmLine(AmLineLength::HalfTile), 3);
+	EXPECT_EQ(AmLine(AmLineLength::QuarterTile), 1);
 }
 
 TEST(Automap, AutomapZoomIn_Max)
 {
+	AutoMapScale = 175;
 	AutoMapScale = 175;
 	AutomapZoomIn();
 	AutomapZoomIn();
 	EXPECT_EQ(AutoMapScale, 200);
-	EXPECT_EQ(AmLine(64), 128);
-	EXPECT_EQ(AmLine(32), 64);
-	EXPECT_EQ(AmLine(16), 32);
-	EXPECT_EQ(AmLine(8), 16);
-	EXPECT_EQ(AmLine(4), 8);
+	EXPECT_EQ(AmLine(AmLineLength::DoubleTile), 32);
+	EXPECT_EQ(AmLine(AmLineLength::FullTile), static_cast<int>(AmLineLength::DoubleTile));
+	EXPECT_EQ(AmLine(AmLineLength::HalfTile), static_cast<int>(AmLineLength::FullTile));
+	EXPECT_EQ(AmLine(AmLineLength::QuarterTile), static_cast<int>(AmLineLength::HalfTile));
 }
 
 TEST(Automap, AutomapZoomOut)
@@ -90,11 +89,10 @@ TEST(Automap, AutomapZoomOut)
 	AutoMapScale = 200;
 	AutomapZoomOut();
 	EXPECT_EQ(AutoMapScale, 175);
-	EXPECT_EQ(AmLine(64), 112);
-	EXPECT_EQ(AmLine(32), 56);
-	EXPECT_EQ(AmLine(16), 28);
-	EXPECT_EQ(AmLine(8), 14);
-	EXPECT_EQ(AmLine(4), 7);
+	EXPECT_EQ(AmLine(AmLineLength::DoubleTile), 28);
+	EXPECT_EQ(AmLine(AmLineLength::FullTile), 14);
+	EXPECT_EQ(AmLine(AmLineLength::HalfTile), 7);
+	EXPECT_EQ(AmLine(AmLineLength::QuarterTile), 3);
 }
 
 TEST(Automap, AutomapZoomOut_Min)
@@ -103,11 +101,10 @@ TEST(Automap, AutomapZoomOut_Min)
 	AutomapZoomOut();
 	AutomapZoomOut();
 	EXPECT_EQ(AutoMapScale, 25);
-	EXPECT_EQ(AmLine(64), 16);
-	EXPECT_EQ(AmLine(32), 8);
-	EXPECT_EQ(AmLine(16), 4);
-	EXPECT_EQ(AmLine(8), 2);
-	EXPECT_EQ(AmLine(4), 1);
+	EXPECT_EQ(AmLine(AmLineLength::DoubleTile), static_cast<int>(AmLineLength::HalfTile));
+	EXPECT_EQ(AmLine(AmLineLength::FullTile), static_cast<int>(AmLineLength::QuarterTile));
+	EXPECT_EQ(AmLine(AmLineLength::HalfTile), 1);
+	EXPECT_EQ(AmLine(AmLineLength::QuarterTile), 0);
 }
 
 TEST(Automap, AutomapZoomReset)
@@ -119,9 +116,8 @@ TEST(Automap, AutomapZoomReset)
 	EXPECT_EQ(AutomapOffset.deltaX, 0);
 	EXPECT_EQ(AutomapOffset.deltaY, 0);
 	EXPECT_EQ(AutoMapScale, 50);
-	EXPECT_EQ(AmLine(64), 32);
-	EXPECT_EQ(AmLine(32), 16);
-	EXPECT_EQ(AmLine(16), 8);
-	EXPECT_EQ(AmLine(8), 4);
-	EXPECT_EQ(AmLine(4), 2);
+	EXPECT_EQ(AmLine(AmLineLength::DoubleTile), static_cast<int>(AmLineLength::FullTile));
+	EXPECT_EQ(AmLine(AmLineLength::FullTile), static_cast<int>(AmLineLength::HalfTile));
+	EXPECT_EQ(AmLine(AmLineLength::HalfTile), static_cast<int>(AmLineLength::QuarterTile));
+	EXPECT_EQ(AmLine(AmLineLength::QuarterTile), 1);
 }