Create ExpandingGridFloodFill.c

ai/ExpandingGridFloodFill.c

@@ -0,0 +1,119 @@
+//
+// Quickly programmed/coded and not tested much.
+
+// Floodfill/seed fill - 
+
+//
+// Around the start position use a for loop(s) with x and y and grow the edges that touch with
+// walkable area. Each loop itteration we use a larger area to loop from(optimalisation!)
+//
+
+
+#include "raylib.h"
+#include <math.h>
+
+int main(void)
+{
+    // Initialization
+    //--------------------------------------------------------------------------------------
+    const int screenWidth = 800;
+    const int screenHeight = 450;
+
+    InitWindow(screenWidth, screenHeight, "raylib example.");
+ 
+    SetTargetFPS(60);               // Set our game to run at 60 frames-per-second
+    //--------------------------------------------------------------------------------------    
+    int mapWidth = 10;
+    int mapHeight = 5;
+    float tileWidth = ceil((float)screenWidth/(float)mapWidth);
+    float tileHeight = ceil((float)screenHeight/(float)mapHeight);
+    int map[5][10] = {  {1,1,1,1,1,1,1,1,1,1},
+                        {1,0,0,0,1,1,0,0,3,1},
+                        {1,0,0,0,1,1,0,1,1,1},
+                        {1,2,0,0,0,0,0,0,0,1},
+                        {1,1,1,1,1,1,1,1,1,1}};
+    bool visitedmap[5][10] = {false};
+    
+    bool pathfound = false;
+    // Main game loop
+    while (!WindowShouldClose())    // Detect window close button or ESC key
+    {
+        // Update
+        //----------------------------------------------------------------------------------
+        if(IsKeyPressed(KEY_SPACE)){
+            // Erase the visited map
+            // find start position (2)
+            // find end position (3)
+            Vector2 posstart;
+            Vector2 posend;
+            for(int y=0;y<mapHeight;y++){
+            for(int x=0;x<mapWidth;x++){
+                visitedmap[y][x] = false;
+                if(map[y][x]==2)posstart = (Vector2){x,y};
+                if(map[y][x]==3)posend = (Vector2){x,y};
+            }}
+            
+            // Flood the map until we find the destination cell/position
+            
+            int mx[] = {0,1,0,-1};//These are the values we use to find the above left and right cells.
+            int my[] = {-1,0,1,0};
+            visitedmap[(int)posstart.x][(int)posstart.y]=true; // we start by setting the vistedmap position where the flood starts true
+            for(int size=1;size<10;size++){ // we check up to a maximum of -10 and 10 size area for the flood.
+                for(int y=posstart.y-size;y<posstart.y+size;y++){
+                for(int x=posstart.x-size;x<posstart.x+size;x++){
+                  if(map[y][x]==0 && visitedmap[y][x]==true){ // if we are on a walkable terrain and we have visited this area before
+                    for(int j=0;j<4;j++){ // loop through the neighbouring cells
+                        int x2=x+mx[j]; // get cell position next to current visited cell
+                        int y2=y+my[j];
+                        if(x2<0 || y2<0 || x2>mapWidth || y2>mapHeight)continue; // if we are outside of bounds then exit and continue with next loop(j)
+                        if(x2==posend.x && y2==posend.y){ // if we find the end position than set a flag
+                            pathfound=true;
+                        }
+
+                        if(map[y2][x2]!=0)continue; // if this cell is not walkable then exit and continue with next loop itteration(j)
+                        visitedmap[y2][x2]=true; // if we are here it means this current cell position is walkable so set the visited map to true
+                    }
+                  }
+                }}
+            }
+        }
+        
+        //----------------------------------------------------------------------------------
+        // Draw
+        //----------------------------------------------------------------------------------
+        BeginDrawing();
+
+            ClearBackground(GREEN);
+                
+            //drawmap
+            for(int y=0;y<5;y++){
+            for(int x=0;x<10;x++){
+                if(map[y][x]==1){ // wall
+                    DrawRectangle(x*tileWidth,y*tileHeight,tileWidth,tileHeight,BLACK);
+                }
+                if(map[y][x]==2){ // start position
+                    DrawRectangle(x*tileWidth,y*tileHeight,tileWidth,tileHeight,RED);
+                    DrawText(FormatText("S"),x*tileWidth+tileWidth/8,y*tileHeight+tileHeight/8,tileWidth,WHITE);
+                }
+                if(map[y][x]==3){ // end position
+                    DrawRectangle(x*tileWidth,y*tileHeight,tileWidth,tileHeight,YELLOW);
+                    DrawText(FormatText("X"),x*tileWidth+tileWidth/8,y*tileHeight+tileHeight/8,tileWidth,WHITE);
+                }
+                if(visitedmap[y][x]==true){
+                    DrawText(FormatText("."),x*tileWidth,y*tileHeight,tileWidth/2,WHITE);
+                }
+            }}
+            if(pathfound)DrawText(FormatText("PAth was found/is reachable.."),0,0,20,WHITE);
+        EndDrawing();
+        //----------------------------------------------------------------------------------
+    }
+
+    // De-Initialization
+    //--------------------------------------------------------------------------------------
+    CloseWindow();        // Close window and OpenGL context
+    //--------------------------------------------------------------------------------------
+
+    return 0;
+
+
+}