add procedural attractors

src/main.zig

@@ -100,20 +100,39 @@ const Emitter = struct {
             }
         }
     }
-    pub fn update(self: *Emitter, texture: rl.Texture2D) void {
+    pub fn update(self: *Emitter,att : []Attractor, texture: rl.Texture2D) void {
         var posx: i32 = 0;
         var posy: i32 = 0;
-        const att: Attractor = .{ .vec = .{ .a = .{ .x = 10, .y = 10, .z = 10 } } };
-        const att2: Attractor = .{ .vec = .{ .a = .{ .x = -200, .y = -200, .z = 0 } } };
+
         var vec2 : rl.Vector2=undefined;
 
-        att.draw();
-        att2.draw();
+        if (rl.isMouseButtonPressed(rl.MouseButton.mouse_button_right)) {
+            std.debug.print("right pressed\n",.{});
+
+            for (att) |*at|
+            {
+                std.debug.print("loop\n",.{});
+                if(at.init_done != 1)
+                {
+                    at.init(.{.a=.{.x=@floatFromInt(rl.getMouseX() - screenWidth / 2),.y=@floatFromInt(rl.getMouseY() - screenHeight / 2),.z=0}});
+        
+                    std.debug.print("attractor allocated\n",.{});
+                    break;
+                }
+            }
+        }
+
+        for (att) |at|
+        {
+            at.draw();
+        }
         for (self.particles) |*p| {
             if (p.show == 1) {
                 p.applyGravity(0);
-                p.applyForce(att.attract(p.*));
-                p.applyForce(att2.attract(p.*));
+                for (att) |at|
+                {
+                    p.applyForce(at.attract(p.*));
+                }
                 p.update();
 
                 posx = @intFromFloat(screenWidth / 2 + p.position.a.x);
@@ -127,6 +146,12 @@ const Emitter = struct {
 };
 const Attractor = struct {
     vec: pr.Vec,
+    init_done : u8 = 0,
+    pub fn init(self : *Attractor, vec : pr.Vec) void
+    {
+        self.vec = vec;
+        self.init_done = 1;
+    }
     pub fn attract(self: Attractor, particle: Particle) pr.Vec {
         const distance = self.vec.sub(particle.position);
         var force: pr.Vec = undefined;
@@ -187,6 +212,7 @@ pub fn main() anyerror!void {
     var plotStr : []u8 = undefined;
     var plotStrBuf : [128]u8 = undefined;
     try plot.log(file,"acceleration, position, velocity, show\n");
+    var att: [10]Attractor = undefined;
 
     while (!rl.windowShouldClose()) { // Detect window close button or ESC key
         rl.beginDrawing();
@@ -213,7 +239,7 @@ pub fn main() anyerror!void {
         try plot.log(file,plotStr);
 
         rl.beginBlendMode(rl.BlendMode.blend_additive);
-        emitter.update(texture);
+        emitter.update(&att,texture);
         rl.endBlendMode();
     }
     plot.close(file);