Viewport preview for batting annotation

Currently it's always set to the same thickness and doesn't update from pset value.

It's currently using zigzag pattern to indicate batting because some techincal limitation of the shader (Error: C6033: Hardware limitation reached, can only emit 256 vertices of this size)

Also added batting to the annotation tool panel.

src/blenderbim/blenderbim/bim/module/drawing/decoration.py

@@ -313,7 +313,15 @@ class BaseDecorator:
         raise NotImplementedError()
 
     def draw_lines(
-        self, context, obj, vertices, indices, topology=None, is_scale_dependant=True, fill_next_vertices=False
+        self,
+        context,
+        obj,
+        vertices,
+        indices,
+        topology=None,
+        is_scale_dependant=True,
+        fill_next_vertices=False,
+        extra_float_kwargs={},
     ):
         # use is_scale_dependant = False if shader is not using uniform viewportDrawingScale
         # otherwise uniform will be discarded during the optimization process
@@ -364,6 +372,9 @@ class BaseDecorator:
             viewport_drawing_scale = 0.00025 * mm_to_px
             self.shader.uniform_float("viewportDrawingScale", viewport_drawing_scale)
 
+        for kwarg, value in extra_float_kwargs.items():
+            self.shader.uniform_float(kwarg, value)
+
         batch.draw(self.shader)
 
     def draw_label(self, context, text, pos, dir, gap=4, center=True, vcenter=False):
@@ -1332,6 +1343,89 @@ class BreakDecorator(BaseDecorator):
         self.draw_lines(context, obj, verts, idxs)
 
 
+class BattingDecorator(BaseDecorator):
+    """Decorator for batting objects
+
+    Uses first two vertices in verts list.
+    """
+
+    objecttype = "BATTING"
+
+    DEF_GLSL = (
+        BaseDecorator.DEF_GLSL
+        + """
+        #define BREAK_LENGTH 32.0
+        #define BREAK_WIDTH 16.0
+        #define PATTERN_SEGMENT_LENGTH 2
+    """
+    )
+
+    GEOM_GLSL = """
+    uniform vec2 winsize;
+    uniform float viewportDrawingScale;
+    uniform float batting_thickness;
+
+    layout(lines) in;
+    layout(line_strip, max_vertices=256) out;
+
+    void main() {
+        vec4 clip2win = matCLIP2WIN();
+        vec4 win2clip = matWIN2CLIP();
+
+        vec4 p0 = gl_in[0].gl_Position, p1 = gl_in[1].gl_Position;
+
+        vec4 p0w = CLIP2WIN(p0), p1w = CLIP2WIN(p1), pmw = (p0w + p1w) * .5;
+        vec4 edge = p1w - p0w, dir = normalize(edge);
+        
+        vec4 gap = dir * 16.0; // TODO: never used?
+        
+        float segment_width = batting_thickness / 2.5;
+        vec2 batting_dimensions = vec2(segment_width, batting_thickness);
+        // make sure to multiply by viewportDrawingScale
+        // so the drawing will stay consistent on zoom in / zoom out
+        mat2 m_edge_space = mat2( dir.xy, dir.yx*vec2(1,-1) ) * viewportDrawingScale;
+        
+        vec2 pattern_segment_data[PATTERN_SEGMENT_LENGTH];
+        // simplified insulation pattern
+        // pattern_segment_data[0] = vec2(0, 1);
+        // pattern_segment_data[1] = vec2(0.5, 0.8);
+        // pattern_segment_data[2] = vec2(0, 0.2);
+        // pattern_segment_data[3] = vec2(0.5, 0);
+        // pattern_segment_data[4] = vec2(1.0, 0.2);
+        // pattern_segment_data[5] = vec2(0.5, 0.8);                
+        // pattern_segment_data[6] = vec2(1.0, 1.0);
+        // zigzag pattern
+        pattern_segment_data[0] = vec2(0, 1);
+        pattern_segment_data[1] = vec2(0, 0);
+
+        int segs = int( ceil( length(edge) / (batting_dimensions.x * viewportDrawingScale) ) ); // amount of segments
+        vec4 p;
+        vec2 p_base, p_cur_ver;
+
+        for (int i = 0; i < segs; i++) {
+            p_base = m_edge_space * (vec2(i, -0.5) * batting_dimensions);
+            for(int j=0; j<PATTERN_SEGMENT_LENGTH; j++) {
+                p_cur_ver = p_base + m_edge_space * (pattern_segment_data[j] * batting_dimensions);
+                p = p0w + vec4(p_cur_ver, 0, 0);
+                gl_Position = WIN2CLIP(p);
+                EmitVertex();
+            }
+        }
+
+        gl_Position = p1;
+        EmitVertex();
+        EndPrimitive();
+    }
+    """
+
+    def decorate(self, context, obj):
+        if obj.data.is_editmode:
+            verts, idxs = self.get_editmesh_geom(obj)
+        else:
+            verts, idxs = self.get_mesh_geom(obj)
+        self.draw_lines(context, obj, verts[:2], idxs, extra_float_kwargs={"batting_thickness": 32.0})
+
+
 class GridDecorator(BaseDecorator):
     objecttype = "GRID"
 
@@ -1788,6 +1882,7 @@ class DecorationsHandler:
         SectionDecorator,
         ElevationDecorator,
         TextDecorator,
+        BattingDecorator,
     ]
 
     installed = None

src/blenderbim/blenderbim/bim/module/drawing/ui.py

@@ -174,7 +174,9 @@ class BIM_PT_drawings(Panel):
                 col.alignment = "LEFT"
                 row2 = col.row(align=True)
                 row2.operator("bim.remove_drawing", icon="X", text="").drawing = active_drawing.ifc_definition_id
-                row2.operator("bim.duplicate_drawing", icon="COPYDOWN", text="").drawing = active_drawing.ifc_definition_id
+                row2.operator(
+                    "bim.duplicate_drawing", icon="COPYDOWN", text=""
+                ).drawing = active_drawing.ifc_definition_id
                 col = row.column()
                 col.alignment = "RIGHT"
                 op = row.operator("bim.open_view", icon="URL", text="")
@@ -417,6 +419,9 @@ class BIM_PT_annotation_utilities(Panel):
         op.data_type = "mesh"
 
         row = layout.row(align=True)
+        op = row.operator("bim.add_annotation", text="Batting", icon="FORCE_FORCE")
+        op.object_type = "BATTING"
+        op.data_type = "mesh"
         op = row.operator("bim.add_annotation", text="Fill Area", icon="NODE_TEXTURE")
         op.object_type = "FILL_AREA"
 

src/blenderbim/blenderbim/tool/drawing.py

@@ -49,6 +49,7 @@ class Drawing(blenderbim.core.tool.Drawing):
     def create_annotation_object(cls, drawing, object_type):
         data_type = {
             "ANGLE": "curve",
+            "BATTING": "mesh",
             "BREAKLINE": "mesh",
             "DIAMETER": "curve",
             "DIMENSION": "curve",