GPencil: Fix unreported error exporting big files in PDF

The exporting was creating a pdf state for each stroke, but this was necessary only for strokes with opacity.

Now, the state is only created when needed and remove the state variable from class.

Also, avoid exporting invisible strokes.

2 files changed, 28 insertions, 13 deletions

diff --git a/source/blender/io/gpencil/intern/gpencil_io_export_pdf.cc b/source/blender/io/gpencil/intern/gpencil_io_export_pdf.cc
index 9b2dc6d12a3..11278a3ccd7 100644
--- a/source/blender/io/gpencil/intern/gpencil_io_export_pdf.cc
+++ b/source/blender/io/gpencil/intern/gpencil_io_export_pdf.cc
@@ -69,7 +69,6 @@ GpencilExporterPDF::GpencilExporterPDF(const char *filename, const GpencilIOPara
 
   pdf_ = nullptr;
   page_ = nullptr;
-  gstate_ = nullptr;
 }
 
 bool GpencilExporterPDF::new_document()
@@ -169,15 +168,27 @@ void GpencilExporterPDF::export_gpencil_layers()
         if (!ED_gpencil_stroke_material_visible(ob, gps)) {
           continue;
         }
-        /* Duplicate the stroke to apply any layer thickness change. */
-        bGPDstroke *gps_duplicate = BKE_gpencil_stroke_duplicate(gps, true, false);
-        MaterialGPencilStyle *gp_style = BKE_gpencil_material_settings(ob,
-                                                                       gps_duplicate->mat_nr + 1);
+        /* Skip invisible lines. */
+        const float fill_opacity = fill_color_[3] * gpl->opacity;
+        const float stroke_opacity = stroke_color_[3] * stroke_average_opacity_get() *
+                                     gpl->opacity;
+        if ((fill_opacity < GPENCIL_ALPHA_OPACITY_THRESH) &&
+            (stroke_opacity < GPENCIL_ALPHA_OPACITY_THRESH)) {
+          continue;
+        }
 
+        MaterialGPencilStyle *gp_style = BKE_gpencil_material_settings(ob, gps->mat_nr + 1);
         const bool is_stroke = ((gp_style->flag & GP_MATERIAL_STROKE_SHOW) &&
                                 (gp_style->stroke_rgba[3] > GPENCIL_ALPHA_OPACITY_THRESH));
         const bool is_fill = ((gp_style->flag & GP_MATERIAL_FILL_SHOW) &&
                               (gp_style->fill_rgba[3] > GPENCIL_ALPHA_OPACITY_THRESH));
+
+        if ((!is_stroke) && (!is_fill)) {
+          continue;
+        }
+
+        /* Duplicate the stroke to apply any layer thickness change. */
+        bGPDstroke *gps_duplicate = BKE_gpencil_stroke_duplicate(gps, true, false);
         prepare_stroke_export_colors(ob, gps_duplicate);
 
         /* Apply layer thickness change. */
@@ -283,29 +294,35 @@ void GpencilExporterPDF::color_set(bGPDlayer *gpl, const bool do_fill)
 {
   const float fill_opacity = fill_color_[3] * gpl->opacity;
   const float stroke_opacity = stroke_color_[3] * stroke_average_opacity_get() * gpl->opacity;
+  const bool need_state = (do_fill && fill_opacity < 1.0f) || (stroke_opacity < 1.0f);
 
   HPDF_Page_GSave(page_);
-  gstate_ = HPDF_CreateExtGState(pdf_);
+  HPDF_ExtGState gstate = (need_state) ? HPDF_CreateExtGState(pdf_) : nullptr;
 
   float col[3];
   if (do_fill) {
     interp_v3_v3v3(col, fill_color_, gpl->tintcolor, gpl->tintcolor[3]);
     linearrgb_to_srgb_v3_v3(col, col);
     CLAMP3(col, 0.0f, 1.0f);
-
-    HPDF_ExtGState_SetAlphaFill(gstate_, clamp_f(fill_opacity, 0.0f, 1.0f));
     HPDF_Page_SetRGBFill(page_, col[0], col[1], col[2]);
+    if (gstate) {
+      HPDF_ExtGState_SetAlphaFill(gstate, clamp_f(fill_opacity, 0.0f, 1.0f));
+    }
   }
   else {
     interp_v3_v3v3(col, stroke_color_, gpl->tintcolor, gpl->tintcolor[3]);
     linearrgb_to_srgb_v3_v3(col, col);
     CLAMP3(col, 0.0f, 1.0f);
 
-    HPDF_ExtGState_SetAlphaFill(gstate_, clamp_f(stroke_opacity, 0.0f, 1.0f));
-    HPDF_ExtGState_SetAlphaStroke(gstate_, clamp_f(stroke_opacity, 0.0f, 1.0f));
     HPDF_Page_SetRGBFill(page_, col[0], col[1], col[2]);
     HPDF_Page_SetRGBStroke(page_, col[0], col[1], col[2]);
+    if (gstate) {
+      HPDF_ExtGState_SetAlphaFill(gstate, clamp_f(stroke_opacity, 0.0f, 1.0f));
+      HPDF_ExtGState_SetAlphaStroke(gstate, clamp_f(stroke_opacity, 0.0f, 1.0f));
+    }
+  }
+  if (gstate) {
+    HPDF_Page_SetExtGState(page_, gstate);
   }
-  HPDF_Page_SetExtGState(page_, gstate_);
 }
 }  // namespace blender::io::gpencil
diff --git a/source/blender/io/gpencil/intern/gpencil_io_export_pdf.hh b/source/blender/io/gpencil/intern/gpencil_io_export_pdf.hh
index 20970151344..89d97f79783 100644
--- a/source/blender/io/gpencil/intern/gpencil_io_export_pdf.hh
+++ b/source/blender/io/gpencil/intern/gpencil_io_export_pdf.hh
@@ -49,8 +49,6 @@ class GpencilExporterPDF : public GpencilExporter {
   HPDF_Doc pdf_;
   /* PDF page. */
   HPDF_Page page_;
-  /* State. */
-  HPDF_ExtGState gstate_;
 
   bool create_document();
   bool add_page();