1 files changed, 111 insertions, 0 deletions
diff --git a/src/kinetics.cpp b/src/kinetics.cpp
new file mode 100644
index 0000000..3444e75
--- /dev/null
+++ b/src/kinetics.cpp
@@ -0,0 +1,111 @@
+#include <kinetics.h>
+void
+generate_color (double *color)
+{
+    int i;
+
+    for (i = 0; i <= 3; i++)
+        color[i] = (int) (drand48 () * 2) / 2.0;
+}
+
+void kinetics_destroy (kinetics_t *kinetics)
+{
+    free(kinetics);
+}
+void kinetics_init (kinetics_t *kinetics)
+{
+    kinetics->angle = drand48 () * 2 * M_PI;
+    kinetics->velocity = MAX_VELOCITY / 8.0 * 7 * drand48 () + MAX_VELOCITY / 8.0;
+    kinetics->x = WIDTH / 2;
+    kinetics->y = HEIGHT / 2;
+    generate_color (kinetics->color);
+
+    kinetics->x_radius = drand48 () * 10 + 5;
+    kinetics->y_radius = drand48 () * 10 + 5;
+    kinetics->x_offset = drand48 () * 10;
+    kinetics->y_offset = drand48 () * 10;
+    kinetics->width = drand48 () * 120 + 30;
+    kinetics->height = drand48 () * 120 + 30;
+
+    generate_color (kinetics->shadow_color);
+    kinetics->rotation = drand48 () * 2 * M_PI;
+
+    kinetics->line_width = 20;//drand48() * 20;
+
+    /* inset shadow */
+    kinetics->shadow_color[0] = 0;
+    kinetics->shadow_color[1] = 0;
+    kinetics->shadow_color[2] = 0;
+    kinetics->shadow_color[3] = 1;
+    kinetics->shadow_x_blur = 5;
+    kinetics->shadow_y_blur = 2;
+
+    kinetics->x_offset = 6;
+    kinetics->y_offset = 1;
+
+    /* spread */
+    kinetics->spread_color[0] = 1;
+    kinetics->spread_color[1] = 1;
+    kinetics->spread_color[2] = 1;
+    kinetics->spread_color[3] = 1;
+    kinetics->spread_x_blur = 5;
+    kinetics->spread_y_blur = 2;
+    kinetics->spread_line_width = 3;
+
+    /* drop shadow */
+    kinetics->drop_color[0] = 0;
+    kinetics->drop_color[1] = 0;
+    kinetics->drop_color[2] = 0;
+    kinetics->drop_color[3] = 0.5;
+    kinetics->drop_x_blur = 10;
+    kinetics->drop_y_blur = 8;
+    kinetics->drop_x_offset = -30;
+    kinetics->drop_y_offset = -5;
+    kinetics->drop_line_width = kinetics->line_width;
+
+}
+
+void kinetics_update (kinetics_t *kinetics, double delta)
+{
+    double x = kinetics->x + cos (kinetics->angle) * kinetics->velocity * delta;
+    double y = kinetics->y + sin (kinetics->angle) * kinetics->velocity * delta;
+    double w = kinetics->width/2;
+    double height = kinetics->height/2;
+
+    if (x + w > WIDTH) {
+    if (kinetics->angle >= 0 && kinetics->angle < M_PI / 2)
+        kinetics->angle =  M_PI - kinetics->angle;
+    else if (kinetics->angle > M_PI / 2 * 3)
+        kinetics->angle -= (kinetics->angle - M_PI /2 * 3) * 2;
+    x = WIDTH - w;
+    }
+
+    if (x - w < 0) {
+    if (kinetics->angle > M_PI / 2 && kinetics->angle <  M_PI)
+        kinetics->angle = M_PI - kinetics->angle;
+    else if (kinetics->angle > M_PI && kinetics->angle < M_PI / 2 * 3)
+        kinetics->angle += (M_PI / 2 * 3 - kinetics->angle) * 2;
+    x = w;
+    }
+
+    if (y + w > HEIGHT) {
+    if (kinetics->angle > 0 && kinetics->angle < 2 * M_PI)
+        kinetics->angle = M_PI * 2 - kinetics->angle;
+    y = HEIGHT - w;
+    }
+
+    if (y - w < 0) {
+    if (kinetics->angle > M_PI && kinetics->angle < M_PI * 2)
+        kinetics->angle = kinetics->angle - (kinetics->angle - M_PI) * 2;
+    y = w;
+    }
+
+    kinetics->x = x;
+    kinetics->y = y;
+
+    kinetics->rotation += M_PI / 9;
+    if (kinetics->rotation > 2 * M_PI)
+    kinetics->rotation -= 2 * M_PI;
+}
+
+