Implement time estimate calculation for SLA printers without tilt.

This commit adds time estimate calculation based on lift and retract.
Calculation with these parameters gets triggered if tilt parameters
are set to null (N/A) in the SLA printer tab.

It also adds a `Time estimate correction` field in the `Corrections`
section of the SLA printer tab to account for processing delays of the
selected printer.

src/libslic3r/Preset.cpp

@@ -709,6 +709,7 @@ static std::vector<std::string> s_Preset_sla_printer_options {
     "elefant_foot_compensation",
     "elefant_foot_min_width",
     "gamma_correction",
+    "time_estimate_correction",
     "min_exposure_time", "max_exposure_time",
     "min_initial_exposure_time", "max_initial_exposure_time", "sla_archive_format", "sla_output_precision",
     //FIXME the print host keys are left here just for conversion from the Printer preset to Physical Printer preset.

src/libslic3r/PrintConfig.cpp

@@ -4105,6 +4105,15 @@ void PrintConfigDef::init_sla_params()
     def->mode = comExpert;
     def->set_default_value(new ConfigOptionFloat(1.0));
 
+    def = this->add("time_estimate_correction", coFloat);
+    def->label = L("Time estimate correction");
+    def->full_label = L("Time estimate correction");
+    def->tooltip  = L("This time will be added for every layer when calculating the printing time estimate. "
+                      "It may correct for any additional delays in the printing process.");
+    def->sidetext = L("s");
+    def->min = 0;
+    def->mode = comAdvanced;
+    def->set_default_value(new ConfigOptionFloat(0.0));
 
     // SLA Material settings.
 

src/libslic3r/PrintConfig.hpp

@@ -1283,6 +1283,7 @@ PRINT_CONFIG_CLASS_DEFINE(
     ((ConfigOptionFloat,                      elefant_foot_compensation))
     ((ConfigOptionFloat,                      elefant_foot_min_width))
     ((ConfigOptionFloat,                      gamma_correction))
+    ((ConfigOptionFloat,                      time_estimate_correction))
     ((ConfigOptionFloatNullable,              fast_tilt_time))
     ((ConfigOptionFloatNullable,              slow_tilt_time))
     ((ConfigOptionFloatNullable,              high_viscosity_tilt_time))

src/libslic3r/SLAPrintSteps.cpp

@@ -1123,6 +1123,23 @@ static int layer_peel_move_time(int layer_height_nm, ExposureProfile p)
     return int(tilt + tower);
 }
 
+namespace {
+template<typename T> static T constrain(T value, T min, T max) {
+    if (value < min)
+        return min;
+    else if (value > max)
+        return max;
+    else
+        return value;
+}
+
+static float constrained_map(float value, float min, float max, float out_min, float out_max) {
+    value = constrain(value, min, max);
+    float t = (value - min) / (max - min);
+    return out_min * (1 - t) + out_max * t;
+}
+}
+
 // Merging the slices from all the print objects into one slice grid and
 // calculating print statistics from the merge result.
 void SLAPrint::Steps::merge_slices_and_eval_stats() {
@@ -1145,6 +1162,8 @@ void SLAPrint::Steps::merge_slices_and_eval_stats() {
     const double init_exp_time = material_config.initial_exposure_time.getFloat();
     const double exp_time      = material_config.exposure_time.getFloat();
 
+    const double time_estimate_correction = printer_config.time_estimate_correction.getFloat();
+
     const int fade_layers_cnt = m_print->m_default_object_config.faded_layers.getInt();// 10 // [3;20]
 
     ExposureProfile below(material_config, 0);
@@ -1166,7 +1185,8 @@ void SLAPrint::Steps::merge_slices_and_eval_stats() {
     // Going to parallel:
     auto printlayerfn = [this,
             // functions and read only vars
-            area_fill, display_area, exp_time, init_exp_time, fast_tilt, slow_tilt, hv_tilt, material_config, delta_fade_time, is_prusa_print, first_slow_layers, below, above, is_printer_with_tilt
+            area_fill, display_area, exp_time, init_exp_time, fast_tilt, slow_tilt, hv_tilt, material_config, delta_fade_time, is_prusa_print, first_slow_layers, below, above,
+            is_printer_with_tilt, time_estimate_correction, fade_layers_cnt,
 
             // write vars
             &layers_info](size_t sliced_layer_cnt)
@@ -1289,6 +1309,38 @@ void SLAPrint::Steps::merge_slices_and_eval_stats() {
 
             // We are done with tilt time, but we haven't added the exposure time yet.
             layer_times += std::max(exp_time, init_exp_time - sliced_layer_cnt * delta_fade_time);
+        } else {
+            bool first_layer = sliced_layer_cnt == 0;
+
+            double layer_exposure_time = constrained_map(sliced_layer_cnt,
+                0, fade_layers_cnt, init_exp_time, exp_time);
+
+            // NOTE: Following times are in minutes and are therefore multiplied by 60
+            double primary_lift_time =
+                (first_layer ? material_config.sla_initial_primary_lift_distance : material_config.sla_primary_lift_distance) /
+                (first_layer ? material_config.sla_initial_primary_lift_speed : material_config.sla_primary_lift_speed) * 60;
+            double secondary_lift_time =
+                (first_layer ? material_config.sla_initial_secondary_lift_distance : material_config.sla_secondary_lift_distance) /
+                (first_layer ? material_config.sla_initial_secondary_lift_speed : material_config.sla_secondary_lift_speed) * 60;
+            double primary_retract_time =
+                (first_layer ? material_config.sla_initial_primary_retract_distance : material_config.sla_primary_retract_distance) /
+                (first_layer ? material_config.sla_initial_primary_retract_speed : material_config.sla_primary_retract_speed) * 60;
+            double secondary_retract_time =
+                (first_layer ? material_config.sla_initial_secondary_retract_distance : material_config.sla_secondary_retract_distance) /
+                (first_layer ? material_config.sla_initial_secondary_retract_speed : material_config.sla_secondary_retract_speed) * 60;
+
+            double wait_times =
+                (first_layer ? material_config.sla_initial_wait_before_lift : material_config.sla_wait_before_lift) +
+                (first_layer ? material_config.sla_initial_wait_after_lift : material_config.sla_wait_after_lift) +
+                (first_layer ? material_config.sla_initial_wait_after_retract : material_config.sla_wait_after_retract);
+
+            layer_times = layer_exposure_time +
+                primary_lift_time + secondary_lift_time +
+                primary_retract_time + secondary_retract_time +
+                wait_times + time_estimate_correction;
+
+            // NOTE: All faded layers are considered slow layers
+            is_fast_layer = sliced_layer_cnt > fade_layers_cnt;
         }
 
         // Collect values for this layer.