Create Heightmap_dividebyline.c

ProcGen/Heightmap_dividebyline.c

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+
+#include "raylib.h"
+#include <math.h>
+
+#define MAP_SIZE 256
+
+int map[MAP_SIZE][MAP_SIZE];
+int heightmap[MAP_SIZE][MAP_SIZE];
+
+void mapline(int x1, int y1, int x2, int y2);
+void scanlinebufferfill(int x, int y, int value);
+
+int main(void)
+{
+    // Initialization
+    //--------------------------------------------------------------------------------------
+    const int screenWidth = 800;
+    const int screenHeight = 512;
+
+    InitWindow(screenWidth, screenHeight, "raylib example.");
+ 
+    SetTargetFPS(60);               // Set our game to run at 60 frames-per-second
+    //--------------------------------------------------------------------------------------
+
+    // Initialise a empty heightmap!
+    for(int y=0;y<MAP_SIZE;y++){
+    for(int x=0;x<MAP_SIZE;x++){
+        heightmap[x][y]=0;
+    }}
+
+    //
+    // The code here below creates the heightmap. We want the height to be with a max height
+    // of 255 and loop the code until this happens. We do this by finding 2 points on a empty
+    // map array. This line will start at an edge and end at an other edge thus dividing the
+    // map into two areas. We then pick a random spot on the map and fill this area. This
+    // filled area is then used to add to the heightmap. (one part of a map divided into two parts
+    // every time) This creates the heightmap.
+    //
+    int highest=0;
+    while(highest<256){
+    //for(int i=0;i<1;i++){
+        for(int y=0;y<MAP_SIZE;y++){
+        for(int x=0;x<MAP_SIZE;x++){
+            map[x][y]=0;
+        }}
+        int side1=GetRandomValue(0,3);
+        int sl[3];
+        int cnt=0;
+        for(int j=0;j<4;j++){
+            if(j==side1)continue;
+            sl[cnt]=j;
+            cnt++;
+        }
+        int side2 = sl[GetRandomValue(0,3)];
+        int x1=0;
+        int y1=0;
+        int x2=0;
+        int y2=0;
+        // get coordinates side 1
+        if(side1 == 0){
+            x1 = 0;
+            y1 = GetRandomValue(0,MAP_SIZE-1);
+        }
+        if(side1 == 1){
+            x1 = GetRandomValue(0,MAP_SIZE-1);
+            y1 = 0;
+        }
+        if(side1 == 2){
+            x1 = MAP_SIZE-1;
+            y1 = GetRandomValue(0,MAP_SIZE-1);
+        }
+        if(side1 == 3){
+            x1 = GetRandomValue(0,MAP_SIZE-1);
+            y1 = MAP_SIZE-1;
+        }
+        // get coordinates side 2
+        if(side2 == 0){
+            x2 = 0;
+            y2 = GetRandomValue(0,MAP_SIZE-1);
+        }
+        if(side2 == 1){
+            x2 = GetRandomValue(0,MAP_SIZE-1);
+            y2 = 0;
+        }
+        if(side2 == 2){
+            x2 = MAP_SIZE-1;
+            y2 = GetRandomValue(0,MAP_SIZE-1);
+        }
+        if(side2 == 3){
+            x2 = GetRandomValue(0,MAP_SIZE-1);
+            y2 = MAP_SIZE-1;
+        }
+        mapline(x1,y1,x2,y2);
+        scanlinebufferfill(GetRandomValue(0,MAP_SIZE-1),GetRandomValue(0,MAP_SIZE-1),1);
+        
+        for(int y=0;y<MAP_SIZE;y++){
+        for(int x=0;x<MAP_SIZE;x++){
+           // Add this line below and remove the other one below that one for a slightly noisy heightmap!
+           //if(map[x][y]==1 && GetRandomValue(0,100)<99)heightmap[x][y]++; 
+           if(map[x][y]==1)heightmap[x][y]++; 
+           // Here we create the heightmap
+           if(heightmap[x][y]>highest)highest=heightmap[x][y];
+        }}
+
+        
+
+    }
+
+
+
+    // Main game loop
+    while (!WindowShouldClose())    // Detect window close button or ESC key
+    {
+        // Update
+        //----------------------------------------------------------------------------------
+        
+        //----------------------------------------------------------------------------------
+        // Draw
+        //----------------------------------------------------------------------------------
+        BeginDrawing();
+
+            ClearBackground(RAYWHITE);
+            int highest=0;
+
+            // Draw the heightmap.
+            for(int y=0;y<MAP_SIZE;y++){
+            for(int x=0;x<MAP_SIZE;x++){
+                if(heightmap[x][y]>highest)highest=heightmap[x][y];
+                if(heightmap[x][y]>0 && heightmap[x][y]<256){
+                    int col=heightmap[x][y];
+                    //col=255;
+                    DrawRectangle(x*2,y*2,2,2,(Color){col,col,col,255});
+                }
+            }
+            }                
+
+        EndDrawing();
+        //----------------------------------------------------------------------------------
+    }
+
+    // De-Initialization
+    //--------------------------------------------------------------------------------------
+    CloseWindow();        // Close window and OpenGL context
+    //--------------------------------------------------------------------------------------
+
+    return 0;
+
+
+}
+
+// A bresenham line function that draws a line inside a mapp[][] array.
+//
+void mapline(int x1, int y1, int x2, int y2){
+    int dx;
+    int dy;
+    int sx;
+    int sy;
+    int e;
+    dx = abs(x2 - x1);
+    sx = -1;
+    if(x1 < x2)sx = 1;
+    dy = abs(y2 - y1);
+    sy = -1;
+    if(y1 < y2)sy = 1;
+    if(dx < dy){
+      e = dx / 2; 
+    }else{ 
+      e = dy / 2;          
+    }
+    bool exitloop=false;
+    while(exitloop == false){
+        //SetColor 255,255,255
+        //DrawPoint x1,y1
+        map[x1][y1]=2;
+        if(x1 == x2){ 
+            if(y1 == y2){
+                exitloop = true;
+            }
+        }
+        if(dx > dy){
+            x1 += sx;
+            e -= dy; 
+            if (e < 0){
+                e += dx;
+                y1 += sy;
+            }
+        }else{
+            y1 += sy; 
+            e -= dx;
+            if(e < 0){
+              e += dy;
+              x1 += sx;
+            }
+        }
+    }
+}
+
+
+
+void scanlinebufferfill(int x, int y, int value){
+    Vector2 list[MAP_SIZE*MAP_SIZE] = {(Vector2){-1,-1}};
+    int listsize=0;
+    list[listsize] = (Vector2){x,y};
+    while(listsize>-1){
+        Vector2 pos = list[listsize];
+        listsize--;
+        
+        map[(int)pos.x][(int){pos.y}]=1;
+        if(pos.y-1>-1 && map[(int)pos.x][(int)pos.y-1]==0){
+            listsize++;
+            list[listsize] = (Vector2){pos.x,pos.y-1};
+        }
+        if(pos.y+1<MAP_SIZE && map[(int)pos.x][(int)pos.y+1]==0){
+            listsize++;
+            list[listsize] = (Vector2){pos.x,pos.y+1};
+        }
+        if(pos.x-1>-1 && map[(int)pos.x-1][(int)pos.y]==0){
+            listsize++;
+            list[listsize] = (Vector2){pos.x-1,pos.y};
+        }
+        if(pos.x+1<MAP_SIZE && map[(int)pos.x+1][(int)pos.y]==0){
+            listsize++;
+            list[listsize] = (Vector2){pos.x+1,pos.y};
+        }
+
+    }
+}