Add texture displacement gizmo and UV editor

src/slic3r/GUI/Jobs/TextureDisplacementPreviewJob.hpp

@@ -0,0 +1,52 @@
+#ifndef slic3r_TextureDisplacementPreviewJob_hpp_
+#define slic3r_TextureDisplacementPreviewJob_hpp_
+
+#include <cstdint>
+#include <functional>
+#include <vector>
+
+#include "libslic3r/TextureDisplacement.hpp"
+#include "libslic3r/TriangleMesh.hpp"
+
+#include "Job.hpp"
+
+namespace Slic3r::GUI {
+
+// Everything process() needs, captured by value on the main thread when the job is queued --
+// mirrors TextureDisplacementBakeInput, but a preview never writes back to the Model.
+struct TextureDisplacementPreviewInput
+{
+    indexed_triangle_set                  base_mesh;
+    std::vector<TextureDisplacementLayer> layers;
+    TextureDisplacementFacetsData         facets_data;
+};
+
+// Computes the true (unbaked) displaced-mesh preview in the background. With several painted
+// layers this is real, non-trivial CPU work (PNG sampling, per-layer vertex welding), which used
+// to run synchronously on every paint stroke and parameter tweak and made editing feel slow with
+// more than one or two layers. Unlike Bake, this never touches the live Model -- a preview is
+// purely informational, there is nothing to commit.
+class TextureDisplacementPreviewJob : public Job
+{
+public:
+    // `generation` is an opaque token the caller controls (typically an incrementing counter):
+    // on_finished should only actually be applied by the caller if it still matches the caller's
+    // current generation when the job completes, so that a burst of edits queuing several of
+    // these jobs in a row can't have an earlier, now-stale result clobber a later one that
+    // finishes first.
+    TextureDisplacementPreviewJob(TextureDisplacementPreviewInput &&input, uint64_t generation,
+                                   std::function<void(indexed_triangle_set, uint64_t)> on_finished);
+
+    void process(Ctl &ctl) override;
+    void finalize(bool canceled, std::exception_ptr &eptr) override;
+
+private:
+    TextureDisplacementPreviewInput                    m_input;
+    uint64_t                                            m_generation;
+    indexed_triangle_set                                m_result;
+    std::function<void(indexed_triangle_set, uint64_t)> m_on_finished;
+};
+
+} // namespace Slic3r::GUI
+
+#endif // slic3r_TextureDisplacementPreviewJob_hpp_