1 files changed, 68 insertions, 0 deletions
diff --git a/src/control.c b/src/control.c
new file mode 100644
index 0000000..d952f7f
--- /dev/null
+++ b/src/control.c
@@ -0,0 +1,68 @@
+#include "control.h"
+#include <stdio.h>
+
+int
+cc_step(cc_t *cc, int steps)
+{
+  float tmp = cc->mod;
+  cc->mod += steps * cc->step;
+
+  if (cc->value+cc->mod > cc->max) {
+    cc->mod = 0;
+    cc->target = cc->max;
+  } else if (cc->value+cc->mod < cc->min) {
+    cc->mod = 0;
+    cc->target = cc->min;
+  }
+
+  return cc->mod != tmp;
+}
+
+void
+cc_prep(cc_t *cc)
+{
+  if (cc->mod) {
+    cc->target = cc->value + cc->mod;
+  }
+}
+
+void
+cc_fix(cc_t *cc)
+{
+  cc->value = cc->target;
+  cc->mod = 0;
+}
+
+void
+cc_reset(cc_t *cc)
+{
+  cc->target = cc->def;
+}
+
+float
+cc_iget(cc_t *cc, unsigned int i, unsigned int max)
+{
+  /*
+    v/t_s: value/time start
+    v/t_e: value/time end
+    y = m*x + b
+    m = (v_e - v_s) / (t_e - t_s)
+    b = v_s - m * t_s
+  */
+  
+  float m = (cc->target - cc->value) / (max - 0);
+
+  float b = cc->value /* + m * 0 */;
+
+  return m * i + b;
+}
+
+const char *
+cc_to_str(cc_t *cc)
+{
+  static char buf[128];
+
+  snprintf(buf, sizeof buf, "[%s:v:%.2f_m:%.2f_t:%.2f]", cc->name, cc->value, cc->mod, cc->target);
+
+  return buf;
+}