Line of sight - rays from player to area tile positions.

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Pakz	Created : 17 October 2020 Language : Raylib c language Line of sight - rays from player to area tile positions.
View on YouTube // // Line of sight or raycasting. // The method I used is by taking an area around the player. In this area each tile is indexed. Than // a invisible bullet is shot from the player position into the direction of this tile. The area underneath // this invisible bullet is marked as visible area. If the bullet hits a wall then the line of sight stops. // I think this method will make sure that every tile is handled! // #include "raylib.h" #include <math.h> typedef struct player{ Vector2 position; }player; float tilewidth; float tileheight; // This is out collision map. bool colmap[10][20] = {false}; bool losmap[10][20] = {false}; // This is our tile map. int map[10][20] = { {1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1}, {1,0,0,0,0,0,0,0,0,0,0,1,0,0,0,1,1,1,1,1}, {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1}, {1,0,0,0,0,0,0,0,0,0,0,1,0,0,0,1,1,1,1,1}, {1,1,1,1,1,1,1,1,0,1,1,1,1,0,0,1,1,1,1,1}, {1,0,0,0,0,0,0,1,0,0,0,1,0,0,0,0,0,0,0,1}, {1,0,0,0,0,0,0,1,0,0,0,1,0,0,0,0,0,0,0,1}, {1,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,1}, {1,0,0,0,0,0,0,1,0,0,0,1,1,1,1,0,0,0,0,1}, {1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1}}; // Our player setup player myplayer = {0}; static void makelos(void); static float getangle(float x1,float y1,float x2,float y2); int main(void) { // Initialization //-------------------------------------------------------------------------------------- const int screenWidth = 800; const int screenHeight = 450; InitWindow(screenWidth, screenHeight, "raylib LOS example."); myplayer.position = (Vector2){5,5}; // Our tile width and height. We use the screen dimension and the map dimension to // get tile dimensions that fill up the entire screen. tilewidth = (float)screenWidth/20.0f; tileheight = (float)screenHeight/10.0f; // Copy the contents of the map into the collision map. for(int y=0;y<10;y++){ for(int x=0;x<20;x++){ if(map[y][x]>0)colmap[y][x]=true; } } SetTargetFPS(60); // Set our game to run at 60 frames-per-second //-------------------------------------------------------------------------------------- // Main game loop while (!WindowShouldClose()) // Detect window close button or ESC key { // Update //---------------------------------------------------------------------------------- // Below here we read the key. If the l/r/u/d cursor is pressed then we check the new position is inside // the array bounds and then we check if the collision map on the new position is not set to flag true on that tile. if(IsKeyPressed(KEY_RIGHT)&& myplayer.position.x+1<20 && colmap[(int)myplayer.position.y][(int)myplayer.position.x+1]==false) { myplayer.position.x+=1; makelos(); } if(IsKeyPressed(KEY_LEFT) && myplayer.position.x-1>-1 && colmap[(int)myplayer.position.y][(int)myplayer.position.x-1]==false) { myplayer.position.x-=1; makelos(); } if(IsKeyPressed(KEY_UP)&& myplayer.position.y-1>-1 && colmap[(int)myplayer.position.y-1][(int)myplayer.position.x]==false) { myplayer.position.y-=1; makelos(); } if(IsKeyPressed(KEY_DOWN) && myplayer.position.y+1<20 && colmap[(int)myplayer.position.y+1][(int)myplayer.position.x]==false) { myplayer.position.y+=1; makelos(); } //---------------------------------------------------------------------------------- // Draw //---------------------------------------------------------------------------------- BeginDrawing(); ClearBackground(RAYWHITE); // Draw our tilemap. for(int y=0;y<10;y++){ for(int x=0;x<20;x++){ if(map[y][x]==1){ DrawRectangle(xtilewidth,ytileheight,tilewidth,tileheight,BLACK); } if(map[y][x]==2){ DrawRectangle(xtilewidth,ytileheight,tilewidth,tileheight,YELLOW); } if(map[y][x]==3){ DrawRectangle(xtilewidth,ytileheight,tilewidth,tileheight,BLUE); } } } // Draw our player DrawRectangle(myplayer.position.xtilewidth,myplayer.position.ytileheight,tilewidth,tileheight,RED); DrawText("Use Cursor Keys to move around..",0,0,20,WHITE); EndDrawing(); //---------------------------------------------------------------------------------- } // De-Initialization //-------------------------------------------------------------------------------------- CloseWindow(); // Close window and OpenGL context //-------------------------------------------------------------------------------------- return 0; } void makelos(){ for(int y=0;y<10;y++){ // erase the map lighted tiles for(int x=0;x<20;x++){ if(map[y][x]!=1)map[y][x]=0; }} float x1 = myplayer.position.y; // x1 and y1 is the tile position of the player float y1 = myplayer.position.x; for(int y=y1-8;y<y1+8;y++){ // x and y is the area we check for line of sight for(int x=x1-8;x<x1+8;x++){ float x4 = x1tilewidth+tilewidth/2; // x4 and y4 is the screen position of the player float y4 = y1tileheight+tileheight/2; float x2=(float)xtilewidth; // x2 and y2 is the screen position of the tiles in the area around the player float y2=(float)ytileheight; float angle = getangle(x2,y2,x4,y4); //get the angle from the player screen position and the tile screen position. bool donot=false; // donot is a variable that is true! if the ray has hit a wall/obstacle for(int z=0;z<200;z++){ // our ray distance traveled (set shorter for circular lighted area!) x4+=cos(angle)1; // x4 and y4 are the rays position(inc!) y4+=sin(angle)1; int x3 = x4/tilewidth; // x3 and y3 is the tile position under the ray int y3 = y4/tileheight; if(x3!=x1 \|\| y3!=y1){ // If the ray is not on the starting tile if(x3>-1 && y3>-1){ // if we are inside the map bounds if(x3<10 && y3<20){ // ,, if(map[x3][y3]==1)donot=true; // If the ray hits a wall/obstacle if(donot==false){ // if we have not hit a obstacle/wall map[x3][y3]=GetRandomValue(2,3); // set the ground to a color(lighted area) } }} } } }} }; // Return the angle from - to in float float getangle(float x1,float y1,float x2,float y2){ return (float)atan2(y2-y1, x2-x1); } --v

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Saturday, 17 October 2020, 09:14
Pakz	I got to say that my new laptop is great to code on! It has 16gb of memory and a fast 8 core amd cpu and fast 1650ti nvidia video card. I still need to go and learn how to do code for more than a single core

Line of sight - rays from player to area tile positions.

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