working dos vga writes!

Common/fix.h

@@ -23,9 +23,6 @@ typedef int32_t com_fix_t;
 
 extern const uint16_t com_fix_sin_lut[128];
 
-void com_fix_run_tests(void);
-void com_fix_run_bench(void);
-
 static inline com_fix_t com_fix_add(com_fix_t a, com_fix_t b) { return a + b; }
 
 static inline com_fix_t com_fix_sub(com_fix_t a, com_fix_t b) { return a - b; }
@@ -64,6 +61,7 @@ static inline com_fix_t com_fix_floor(com_fix_t const a) {
 com_fix_t com_fix_sqrt(com_fix_t a);
 
 /* Approximated using LUT. */
+/* Integer part only houses sign. */
 /* TODO: test whether linearly interpolated version could be default. */
 /*       things like camera movement can be jarring if done without.*/
 /* https://namoseley.wordpress.com/2015/07/26/sincos-generation-using-table-lookup-and-iterpolation/
@@ -90,9 +88,11 @@ static inline com_fix_t com_fix_sin(com_fix_t q) {
   }
 }
 
+static inline com_fix_t com_fix_sin_from_lut(uint8_t l) {
+  return com_fix_sin_lut[l];
+}
+
 /* Implemented over sin, as to share one single LUT. */
-/* Additionally, optimizer probably can collapse some math for combined sincos
- * case. */
 static inline com_fix_t com_fix_cos(com_fix_t a) {
   return com_fix_sin(a + COM_FIX_PIHALF);
 }