diff --git a/Makefile b/Makefile
index 810db76..10234cf 100644
--- a/Makefile
+++ b/Makefile
@@ -103,10 +103,10 @@ MAIN_OBJS = \
 	src/glad.o \
 	src/opengl.o \
 	src/render.o \
-	src/collision.o \
 	src/collision2.o \
 	src/update.o \
 	src/unparse.o \
+	src/color.o \
 	$(patsubst %.glsl,%.glsl.o,$(wildcard src/shader/*.glsl)) \
 	$(patsubst %.data,%.data.o,$(wildcard src/level/*.data)) \
 	$(patsubst %.data,%.data.o,$(wildcard src/font/*.data)) \
diff --git a/include/color.hpp b/include/color.hpp
new file mode 100644
index 0000000..ff2eb36
--- /dev/null
+++ b/include/color.hpp
@@ -0,0 +1,5 @@
+#pragma once
+
+#include "math/float_types.hpp"
+
+vec3 hsv_to_rgb(float h, float s, float v);
diff --git a/include/state.h b/include/state.h
index 4d51e21..bbe7616 100644
--- a/include/state.h
+++ b/include/state.h
@@ -15,6 +15,7 @@ extern "C" {
     float ball_y;
     float ball_dx;
     float ball_dy;
+    double launch_time;
   };
 
   #define MAX_BALLS 20
diff --git a/src/color.cpp b/src/color.cpp
new file mode 100644
index 0000000..a7a935d
--- /dev/null
+++ b/src/color.cpp
@@ -0,0 +1,26 @@
+#include "color.hpp"
+
+vec3 hsv_to_rgb(float h, float s, float v)
+{
+  if (s == 0.0)
+    return vec3(v, v, v);
+  int i = h * 6.0f;
+  float f = (h * 6.0f) - i;
+  float p = v * (1.0f - s);
+  float q = v * (1.0f - s * f);
+  float t = v * (1.0f - s * (1.0f - f));
+  i = i % 6;
+  if (i == 0)
+    return vec3(v, t, p);
+  if (i == 1)
+    return vec3(q, v, p);
+  if (i == 2)
+    return vec3(p, v, t);
+  if (i == 3)
+    return vec3(p, q, v);
+  if (i == 4)
+    return vec3(t, p, v);
+  if (i == 5)
+    return vec3(v, p, q);
+  return vec3(0, 0, 0);
+}
diff --git a/src/render.cpp b/src/render.cpp
index 092564a..aa154b1 100644
--- a/src/render.cpp
+++ b/src/render.cpp
@@ -5,9 +5,8 @@
 #include "glad/glad.h"
 
 #include "unparse.h"
-#include "collision.hpp"
-#include "collision2.hpp"
 #include "render.hpp"
+#include "color.hpp"
 #include "math/float_types.hpp"
 #include "math/transform.hpp"
 
@@ -234,7 +233,11 @@ void render(mesh paddle_mesh,
 
     mat4x4 trans = a * t * rx;
     mat3x3 normal_trans = submatrix(rx, 3, 3);
-    vec4 base_color = vec4(0.5f, 0.5f, 0.5f, 1.0f);
+    //vec4 base_color = vec4(0.5f, 0.5f, 0.5f, 1.0f);
+    float hue = state->time - ball.launch_time;
+    hue = hue - floorf(hue);
+    vec3 c = hsv_to_rgb(hue, 1.0f, 1.0f);
+    vec4 base_color = vec4(c.x, c.y, c.z, 1.0f);
     //vec3 light_pos = vec3(-1, -1, 1);
 
     glBindBuffer(GL_ARRAY_BUFFER, ball_mesh.vtx);
diff --git a/src/update.cpp b/src/update.cpp
index f6442a5..3df5afd 100644
--- a/src/update.cpp
+++ b/src/update.cpp
@@ -49,6 +49,7 @@ void launch_ball(struct game_state * state, double time)
   ball.ball_y = 25.0f;
   ball.ball_dx = d.x;
   ball.ball_dy = -d.y;
+  ball.launch_time = time;
 
   state->balls_launched += 1;
 }
@@ -122,6 +123,8 @@ void update_ball(struct game_state * state, struct ball_state& ball, double time
     bool collided = aabb_circle_collision(paddle_position, ball_position, paddle_bounds, &cd);
     if (collided) {
       ball_collision_response(ball, cd);
+      ball.ball_y = 25.0f;
+      ball.ball_dy = -fabsf(ball.ball_dy);
     }
   }