CURA- 12556 formula parser in cura engine

CMakeLists.txt

@@ -51,6 +51,7 @@ set(engine_SRCS # Except main.cpp.
         src/FffProcessor.cpp
         src/gcodeExport.cpp
         src/GCodePathConfig.cpp
+        src/GcodeTemplateResolver.cpp
         src/infill.cpp
         src/InterlockingGenerator.cpp
         src/InsetOrderOptimizer.cpp
@@ -142,6 +143,7 @@ set(engine_SRCS # Except main.cpp.
         src/settings/FlowTempGraph.cpp
         src/settings/MeshPathConfigs.cpp
         src/settings/PathConfigStorage.cpp
+        src/settings/SettingContainersEnvironmentAdapter.cpp
         src/settings/Settings.cpp
         src/settings/ZSeamConfig.cpp
 
@@ -251,6 +253,8 @@ find_package(fmt REQUIRED)
 find_package(range-v3 REQUIRED)
 find_package(scripta REQUIRED)
 find_package(PNG REQUIRED)
+find_package(cura-formulae-engine REQUIRED)
+
 if (NOT EMSCRIPTEN)
     find_package(TBB REQUIRED)
 endif ()
@@ -275,6 +279,7 @@ target_link_libraries(_CuraEngine
         boost::boost
         scripta::scripta
         PNG::PNG
+        cura-formulae-engine::cura-formulae-engine
         $<$<NOT:$<BOOL:${EMSCRIPTEN}>>:onetbb::onetbb>
         $<$<TARGET_EXISTS:semver::semver>:semver::semver>
         $<$<TARGET_EXISTS:curaengine_grpc_definitions::curaengine_grpc_definitions>:curaengine_grpc_definitions::curaengine_grpc_definitions>

conandata.yml

@@ -1,9 +1,11 @@
 version: "5.14.0-alpha.0"
 commit: "unknown"
 requirements:
+  - "cura-formulae-engine/1.0.0"
   - "scripta/[>=1.1.0]@ultimaker/testing"
   - "libpng/1.6.48"
   - "onetbb/2022.2.0"
+  - "zeus_expected/[>=1.1.1]"
 requirements_arcus:
   - "arcus/5.11.1"
 requirements_plugins:

include/GcodeTemplateResolver.h

@@ -0,0 +1,31 @@
+// Copyright (c) 2026 UltiMaker
+// CuraEngine is released under the terms of the AGPLv3 or higher
+
+#ifndef GCODETEMPLATERESOLVER_H
+#define GCODETEMPLATERESOLVER_H
+
+#include <cura-formulae-engine/eval.h>
+#include <optional>
+#include <string>
+#include <unordered_map>
+
+namespace cura::GcodeTemplateResolver
+{
+
+/*!
+ * Resolve a raw GCode template that can contains conditional code and complex formulas
+ * @param input The raw GCode template text
+ * @param context_extruder_nr The default contextual extruder number, which should be the current extruder number when dealing when an extruder start/end GCode, and nullopt when
+ *                            dealing with the global machine start/end gcode
+ * @param extra_settings Extra settings to be used locally for the resolving, even though they don't exist as actual settings
+ * @return The fully resolved GCode template, or the raw template if an error occurred. Also, if the given input is empty, the result will also be fully empty. However, if it
+ *         has some content, the function ensures that the result contains and end-of-line at the end so that it can be inserted directly in a GCode without having to insert one.
+ */
+std::string resolveGCodeTemplate(
+    const std::string& input,
+    const std::optional<int> context_extruder_nr = std::nullopt,
+    const std::unordered_map<std::string, CuraFormulaeEngine::eval::Value>& extra_settings = {});
+
+} // namespace cura::GcodeTemplateResolver
+
+#endif

include/gcodeExport.h

@@ -345,7 +345,9 @@ class GCodeExport : public NoCopy
      */
     void writeLayerCountComment(const size_t layer_count);
 
-    void writeLine(const char* line);
+    void writeLine(const std::string& line);
+
+    void writeRaw(const std::string& gcode);
 
     /*!
      * Reset the current_e_value to prevent too high E values.
@@ -608,7 +610,7 @@ class GCodeExport : public NoCopy
      */
     void switchExtruder(size_t new_extruder, const RetractionConfig& retraction_config_old_extruder, coord_t perform_z_hop = 0);
 
-    void writeCode(const char* str);
+    void writeCode(const std::string& str);
 
     /*!
      * Write code while temporarily ensuring absolute extrusion mode.
@@ -619,7 +621,7 @@ class GCodeExport : public NoCopy
      *
      * \param str The code string to write
      */
-    void writeCodeWithAbsoluteExtrusion(const char* str);
+    void writeCodeWithAbsoluteExtrusion(const std::string& str);
 
     void resetExtruderToPrimed(const size_t extruder, const double initial_retraction);
 
@@ -709,9 +711,16 @@ class GCodeExport : public NoCopy
     /*!
      * Finish the gcode: turn fans off, write end gcode and flush all gcode left in the buffer.
      *
-     * \param endCode The end gcode to be appended at the very end.
+     * \param end_code The end gcode to be appended at the very end.
+     */
+    void finalize(const std::string& end_code);
+
+    /*!
+     * Finish the extruder gcode: write extrude rend gcode.
+     *
+     * \param extruder_end_code The end gcode to be appended at the end.
      */
-    void finalize(const char* endCode);
+    void finalizeExtruder(const std::string& extruder_end_code);
 
     /*!
      * Get amount of material extruded since last wipe script was inserted.

include/settings/SettingContainersEnvironmentAdapter.h

@@ -0,0 +1,38 @@
+// Copyright (c) 2026 UltiMaker
+// CuraEngine is released under the terms of the AGPLv3 or higher
+
+#ifndef SETTINGS_SETTINGCONTAINERENVIRONMENTADAPTER_H
+#define SETTINGS_SETTINGCONTAINERENVIRONMENTADAPTER_H
+
+#include <cura-formulae-engine/ast/ast.h>
+
+namespace cura
+{
+
+class Settings;
+
+/*!
+ * Adapter class used to expose the engine settings stack to the formulae engine resolving system
+ */
+class SettingContainersEnvironmentAdapter : public CuraFormulaeEngine::env::Environment
+{
+public:
+    /*!
+     * Base constructor
+     * @param settings The settings to be used as the base contextual stack
+     */
+    explicit SettingContainersEnvironmentAdapter(const Settings& settings);
+
+    [[nodiscard]] std::optional<CuraFormulaeEngine::eval::Value> get(const std::string& setting_id) const override;
+
+    [[nodiscard]] bool has(const std::string& key) const override;
+
+    [[nodiscard]] std::unordered_map<std::string, CuraFormulaeEngine::eval::Value> getAll() const override;
+
+private:
+    const Settings& settings_;
+};
+
+} // namespace cura
+
+#endif

include/settings/Settings.h

@@ -90,10 +90,11 @@ class Settings
      * If this returns ``false``, that means that the setting would be obtained
      * via some inheritance.
      * \param key The setting to check.
+     * \param parent_lookup Indicates whether the setting should also be looked up in the parent settings, as the get() would
      * \return Whether that setting is contained in this particular Settings
      * instance (``true``) or would be obtained via inheritance (``false``).
      */
-    bool has(const std::string& key) const;
+    bool has(const std::string& key, const bool parent_lookup = false) const;
 
     /*
      * Change the parent settings object.

src/FffGcodeWriter.cpp

@@ -19,6 +19,7 @@
 #include "Application.h"
 #include "ExtruderTrain.h"
 #include "FffProcessor.h"
+#include "GcodeTemplateResolver.h"
 #include "InsetOrderOptimizer.h"
 #include "LayerPlan.h"
 #include "PrimeTower/PrimeTower.h"
@@ -4349,7 +4350,7 @@ void FffGcodeWriter::finalize()
 
     if (! extruder_end_code.empty())
     {
-        gcode.writeCodeWithAbsoluteExtrusion(extruder_end_code.c_str());
+        gcode.finalizeExtruder(extruder_end_code);
     }
 
     if (mesh_group_settings.get<bool>("machine_heated_bed"))
@@ -4392,13 +4393,17 @@ void FffGcodeWriter::finalize()
         gcode.writeJerk(mesh_group_settings.get<Velocity>("machine_max_jerk_xy"));
     }
 
-    const auto end_gcode = mesh_group_settings.get<std::string>("machine_end_gcode");
+    // Replace the setting tokens in start and end g-code.
+    // Use values from the first used extruder by default so we get the expected temperatures
+    auto machine_end_gcode = mesh_group_settings.get<std::string>("machine_end_gcode");
+    auto initial_extruder_nr = Application::getInstance().current_slice_->scene.settings.get<int>("initial_extruder_nr");
+    machine_end_gcode = GcodeTemplateResolver::resolveGCodeTemplate(machine_end_gcode, initial_extruder_nr);
 
-    if (end_gcode.length() > 0 && mesh_group_settings.get<bool>("relative_extrusion"))
+    if (! machine_end_gcode.empty() && mesh_group_settings.get<bool>("relative_extrusion"))
     {
         gcode.writeExtrusionMode(false); // ensure absolute extrusion mode is set before the end gcode
     }
-    gcode.finalize(end_gcode.c_str());
+    gcode.finalize(machine_end_gcode);
 
     // set extrusion mode back to "normal"
     gcode.resetExtrusionMode();