From: hgn <hgodden00@gmail.com>
Date: Wed, 22 Sep 2021 17:22:42 +0000 (+0100)
Subject: create tile validator
X-Git-Url: https://harrygodden.com/git/?a=commitdiff_plain;h=9fb455711b9b5fa8521fca8c03525de327e66e49;p=fishladder.git

create tile validator
---

diff --git a/fishladder.c b/fishladder.c
index 1934014..e8f8014 100644
--- a/fishladder.c
+++ b/fishladder.c
@@ -257,6 +257,91 @@ void vg_free(void)
 	map_free();
 }
 
+static int cell_interactive( v2i co )
+{
+	// Bounds check
+	if( co[0] < 2 || co[0] >= world.w-2 || co[1] < 2 || co[1] >= world.h-2 )
+		return 0;
+
+	// Flags check
+	if( world.data[ world.w*co[1] + co[0] ].state & (FLAG_WALL|FLAG_INPUT|FLAG_OUTPUT) )
+		return 0;
+
+	// List of 3x3 configurations that we do not allow
+	static u32 invalid_src[][9] = 
+	{ 
+		{ 0,1,0,
+		  1,1,1,
+		  0,1,0 
+		},
+		{ 0,0,0,
+		  0,1,1,
+		  0,1,1
+		},
+		{ 0,0,0,
+		  1,1,0,
+		  1,1,0
+		},
+		{ 0,1,1,
+		  0,1,1,
+		  0,0,0
+		},
+		{ 1,1,0,
+		  1,1,0,
+		  0,0,0
+		},
+		{ 0,1,0,
+		  0,1,1,
+		  0,1,0
+		},
+		{ 0,1,0,
+		  1,1,0,
+		  0,1,0
+		}
+	};
+	
+	// Statically compile invalid configurations into bitmasks
+	static u32 invalid[ vg_list_size(invalid_src) ];
+	
+	for( int i = 0; i < vg_list_size(invalid_src); i ++ )
+	{
+		u32 comped = 0x00;
+	
+		for( int j = 0; j < 3; j ++ )
+			for( int k = 0; k < 3; k ++ )
+				comped |= invalid_src[i][ j*3+k ] << ((j*5)+k);
+		
+		invalid[i] = comped;
+	}
+
+	// Extract 5x5 grid surrounding tile
+	u32 blob = 0x1000;
+	for( int y = co[1]-2; y < co[1]+3; y ++ )
+		for( int x = co[0]-2; x < co[0]+3; x ++ )
+		{                
+			struct cell *cell = &world.data[ world.w*y + x ];
+
+			if( cell && (cell->state & (FLAG_CANAL|FLAG_INPUT|FLAG_OUTPUT)) )
+				blob |= 0x1 << ((y-(co[1]-2))*5 + x-(co[0]-2));
+		}
+
+	// Run filter over center 3x3 grid to check for invalid configurations
+	int kernel[] = { 0, 1, 2, 5, 6, 7, 10, 11, 12 };
+	for( int i = 0; i < vg_list_size(kernel); i ++ )
+	{
+		if( blob & (0x1 << (6+kernel[i])) )
+		{
+			u32 window = blob >> kernel[i];
+
+			for( int j = 0; j < vg_list_size(invalid); j ++ )
+				if((window & invalid[j]) == invalid[j])
+			return 0;
+		}
+	}
+
+	return 1;
+}
+
 void vg_update(void)
 {
 	float ratio = (float)vg_window_y / (float)vg_window_x;
@@ -279,21 +364,13 @@ void vg_update(void)
 	int tile_x = floorf( tile_pos[0] );
 	int tile_y = floorf( tile_pos[1] );
 	
-	if( tile_x >= 2 && tile_x < world.w-2 && tile_y >= 2 && tile_y <= world.h-2 )
+	if( cell_interactive( (v2i){ tile_x, tile_y } ))// tile_x >= 2 && tile_x < world.w-2 && tile_y >= 2 && tile_y <= world.h-2 )
 	{
 		world.selected = tile_y * world.w + tile_x;
 		
-		struct cell *cell = &world.data[tile_y*world.w+tile_x];
-		if( cell->state & (FLAG_WALL|FLAG_INPUT|FLAG_OUTPUT) )
+		if( vg_get_button_down("primary") )
 		{
-			world.selected = -1;
-		}
-		else
-		{
-			if( vg_get_button_down("primary") )
-			{
-				cell->state ^= FLAG_CANAL;
-			}
+			world.data[ world.selected ].state ^= FLAG_CANAL;
 		}
 	}
 	else
@@ -317,7 +394,7 @@ void vg_update(void)
 				struct cell *cell = &world.data[y*world.w+x];
 
 				if( cell->state & FLAG_INPUT )
-					cell->water[ buffer_next ] = 8;
+					cell->water[ buffer_next ] = 16;
 				else
 				{
 					int has_source = 0;