mk2: code_part1/OSTC_code_c_part2/p2

comparison code_part1/OSTC_code_c_part2/p2_deco.c @ 562:56753ea6a791 bug_deco_clearing_missed_stops

Cleaning LOW gf reference in deco model

author	JeanDo
date	Sat, 25 Feb 2012 15:13:26 +0100
parents	57622cb0d80f
children	7bec4cf28cc7

comparison

equal deleted inserted replaced

-:57622cb0d80f
+:56753ea6a791
 // 2011/04/27: [jDG] Fixed char_O_gradient_factor calculation when model uses gradient-factor.
 // 2011/05/02: [jDG] Added "Future TTS" function (CF58).
 // 2011/05/17: [jDG] Various cleanups.
 // 2011/08/08: [jDG] Computes CNS during deco planning ascent.
 // 2011/11/24: [jDG] Slightly faster and better NDL computation.
-// 2011/12/17: [mH] Remove of the useless debug stuff
+// 2011/12/17: [mH]  Remove of the useless debug stuff
 // 2012/02/24: [jDG] Remove missed stop bug.
+// 2012/02/25: [jDG] Looking for a more stable LOW grad factor reference.
 //
 // TODO:
 //  + Allow to abort MD2 calculation (have to restart next time).
 //
 // Literature:
 static float			temp_limit;
 static float			GF_low;
 static float			GF_high;
 static float			GF_delta;
-static float            low_depth;                  // Depth of deepest stop
 static float			locked_GF_step;             // GF_delta / low_depth
 static unsigned char    temp_depth_limit;
+static unsigned char    low_depth;                  // Depth of deepest stop
 // Simulation context: used to predict ascent.
 static unsigned char	sim_lead_tissue_no;         // Leading compatiment number.
 static float			sim_lead_tissue_limit;      // Buhlmann tolerated pressure.
 assert( depth >= -0.2 );        // Allow for 200mbar of weather change.
 //---- ZH-L16 + GRADIENT FACTOR model ------------------------------------
 	if( char_I_deco_model != 0 )
 	{
+overlay unsigned char first_stop = 0;
+overlay float p;
 if( depth >= low_depth )
 sim_limit( GF_low );
 else
 sim_limit( GF_high - depth * locked_GF_step );
-// Stops are needed ?
+p = sim_lead_tissue_limit - pres_surface;
-if( sim_lead_tissue_limit > pres_surface )
+if( p <= 0.0f )
-{
+goto no_deco_stop;          // We can surface directly...
-// Compute tolerated depth, for the leading tissue [metre]:
-overlay float depth_tol = (sim_lead_tissue_limit - pres_surface) * BAR_TO_METER;
+p *= BAR_TO_METER;
-overlay unsigned char first_stop;
+if( p < min_depth )
+goto no_deco_stop;          // First stop is higher than 1' ascent.
-// 2012-02-24 NOTE: Do not discard a stop just because we get shallower !
-//     ---> Better to keep it red until the situation is cleared.
+first_stop = 3 * (short)(0.99999 + p*0.333333);
+assert( first_stop < 128 );
-// Deepest stop, in multiples of 3 metres.
-first_stop = 3 * (short)(0.99999 + depth_tol * 0.33333 );
+// Apply correction for the shallowest stop.
-assert( first_stop < 128 );
+if( first_stop == 3 )                           // new in v104
+first_stop = char_I_depth_last_deco;        // Use last 3m..6m instead.
-// Is it a new deepest needed stop ? If yes this is the reference for
-// the varying gradient factor. So reset that:
+// Store the deepest point needing a deco stop as the LOW reference for GF.
-if( depth_tol > min_depth && depth_tol > low_depth )
+// NOTE: following stops will be validated using this LOW-HIGH gf scale,
-{
+//       so if we want to keep coherency, we should not validate this stop
-// Store the deepest stop depth, as reference for GF_low.
+//       yet, but apply the search as all the following stops afterward.
-low_depth = depth_tol;
+if( first_stop > low_depth )
-locked_GF_step = GF_delta / low_depth;
+{
-}
+low_depth = first_stop;
+locked_GF_step = GF_delta / low_depth;
-// Apply correction for the shallowest stop.
+}
-if( first_stop == 3 )                           // new in v104
-first_stop = char_I_depth_last_deco;        // Use last 3m..6m instead.
+// We have a stop candidate.
+// But maybe ascending to the next stop will diminish the constraint,
-// Because gradient factor at first_stop might be bigger than at
+// because the GF might decrease more than the preassure gradient...
-// current depth, we might ascent a bit more.
+while(first_stop > 0)
-// Hence, check all stops until one is indeed higher than tolerated presure:
+{
-while(first_stop > 0)
+overlay unsigned char next_stop;            // Next depth (0..90m)
-{
+overlay float pres_stop;                    // Next pressure (bar)
-overlay unsigned char next_stop;            // Next index (0..30)
-overlay float pres_stop;                    // Next depth (0m..90m)
+// Check max speed, or reaching surface.
+if( first_stop <= min_depth )
-// Check max speed, or reaching surface.
+goto no_deco_stop;
-if( first_stop <= min_depth )
-break;
+if( first_stop <= char_I_depth_last_deco )  // new in v104
+next_stop = 0;
-// So, there is indeed a stop needed:
+else if( first_stop == 6 )
-need_stop = 1;
+next_stop = char_I_depth_last_deco;
+else
-if( first_stop <= char_I_depth_last_deco )  // new in v104
+next_stop = first_stop - 3;             // Index of next (upper) stop.
-next_stop = 0;
-else if( first_stop == 6 )
+// Just a check we are indeed above LOW ref.
-next_stop = char_I_depth_last_deco;
+assert( next_stop < low_depth );
-else
-next_stop = first_stop - 3;             // Index of next (upper) stop.
+// Total preassure at the new stop candidate:
+pres_stop =  next_stop * METER_TO_BAR
-	    pres_stop =  next_stop * METER_TO_BAR
+	              + pres_surface;
-	              + pres_surface;
+// Keep GF_low until a first stop depth is found:
-// Keep GF_low until a first stop depth is found:
+sim_limit( GF_high - next_stop * locked_GF_step );
-if( next_stop >= low_depth )
-sim_limit( GF_low );
+// Check upper limit (lowest pressure tolerated):
-else
+if( sim_lead_tissue_limit >= pres_stop )    // check if ascent to next deco stop is ok
-// current GF is GF_high - alpha (GF_high - GF_low)
+goto deco_stop_found;
-// With alpha = currentDepth / maxDepth, hence in [0..1]
-sim_limit( GF_high - next_stop * locked_GF_step );
+// Else, validate that stop and loop...
+first_stop = next_stop;
-// upper limit (lowest pressure tolerated):
+}
-if( sim_lead_tissue_limit >= pres_stop )    // check if ascent to next deco stop is ok
+assert( first_stop == 0 );
-break;
+no_deco_stop:
-// Else, validate that stop and loop...
+		temp_depth_limit = 0;
-first_stop = next_stop;
+goto done;
-}
+// next stop is the last validated depth found, aka first_stop
-// next stop is the last validated depth found, aka first_stop
+deco_stop_found:
-temp_depth_limit = first_stop;                  // Stop depth, in metre.
+need_stop = 1;                  // Hit.
-}
+temp_depth_limit = first_stop;  // Stop depth, in meter.
-else
-			temp_depth_limit = 0;                           // stop depth, in metre.
+done:
+;
 	}
 	else //---- ZH-L16 model -------------------------------------------------
 	{
 overlay float pres_gradient;
 char_O_deco_status = 0;     // Calc bottom-time/nullzeit next iteration.
 // Values that should be reset just once for the full real dive.
 // This is used to record the lowest stop for the whole dive,
 // Including ACCROSS all simulated ascent.
-low_depth = 0.0;
+// NOTE: Use a default of 6m (like the 10m in the DR5 code).
+//       Because this produces less babling stops at the
+//       beginning of the decompression. But putting a value too high
+//       have the immediat effect of using lower GF for shallow dives...
+low_depth = 6;
 // Reset gas switch history.
 backup_gas_used  = sim_gas_last_used  = 0;
 backup_gas_depth = sim_gas_last_depth = 0;
 backup_gas_delay = sim_gas_delay = 0;
 	if( char_I_deco_model != 0 )        // calculate relative gradient factor
 	{
 overlay float rgf;
-		if( low_depth < 1.5 )
+		if( low_depth < 3 )
 			rgf = GF_high;
 else
 {
 overlay float temp1 = low_depth * METER_TO_BAR;
 overlay float temp2 = pres_respiration - pres_surface;

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comparison code_part1/OSTC_code_c_part2/p2_deco.c @ 562:56753ea6a791 bug_deco_clearing_missed_stops