Use gl_InstanceID instead of hacking triangle_strip

manimlib/camera/camera.py

@@ -457,7 +457,10 @@ class Camera(object):
             self.ctx.enable(moderngl.BLEND)
             self.ctx.blend_func = moderngl.ONE, moderngl.ONE
             self.ctx.blend_equation = moderngl.FUNC_SUBTRACT
-            render_group["vao"].render(int(shader_wrapper.render_primitive))
+            render_group["vao"].render(
+                int(shader_wrapper.render_primitive),
+                instances=2,
+            )
             self.ctx.blend_func = moderngl.DEFAULT_BLENDING
             self.ctx.blend_equation = moderngl.FUNC_ADD
             self.fbo.use()

manimlib/mobject/types/vectorized_mobject.py

@@ -1183,7 +1183,6 @@ class VMobject(Mobject):
         for submob in family:
             if submob.has_fill():
                 submob.data["base_point"][:] = submob.data["point"][0]
-                # submob.data["base_color"][:] = submob.data["fill_color"][0]
                 fill_datas.append(submob.data[fill_names])
                 # Add dummy
                 fill_datas.append(submob.data[fill_names][-1:])

manimlib/shaders/quadratic_bezier_fill/frag.glsl

@@ -1,9 +1,7 @@
 #version 330
 
 in vec4 color;
-in float fill_all;  // Either 0 or 1
-
-in float orientation;
+in float fill_all;
 in vec2 uv_coords;
 
 out vec4 frag_color;
@@ -11,11 +9,9 @@ out vec4 frag_color;
 void main() {
     if (color.a == 0) discard;
     frag_color = color;
-    if (orientation == 0) return;
-
-    float x0 = uv_coords.x;
-    float y0 = uv_coords.y;
-    float Fxy = y0 - x0 * x0;
-    if(orientation * Fxy < 0) discard;
+    if (bool(fill_all)) return;
 
+    float x = uv_coords.x;
+    float y = uv_coords.y;
+    if(y - x * x < 0) discard;
 }

manimlib/shaders/quadratic_bezier_fill/geom.glsl

@@ -1,7 +1,7 @@
 #version 330
 
 layout (triangles) in;
-layout (triangle_strip, max_vertices = 7) out;
+layout (triangle_strip, max_vertices = 3) out;
 
 uniform float anti_alias_width;
 uniform float pixel_size;
@@ -11,11 +11,10 @@ in vec3 verts[3];
 in vec4 v_color[3];
 in vec3 v_base_point[3];
 in float v_vert_index[3];
-
+in float v_inst_id[3];
 
 out vec4 color;
-
-out float orientation;
+out float fill_all;
 // uv space is where the curve coincides with y = x^2
 out vec2 uv_coords;
 
@@ -38,31 +37,29 @@ void main(){
     // actually only need every other strip element
     if (int(v_vert_index[0]) % 2 == 1) return;
 
-    // Curves are marked as eneded when the handle after
+    // Curves are marked as ended when the handle after
     // the first anchor is set equal to that anchor
     if (verts[0] == verts[1]) return;
 
     vec3 unit_normal = get_unit_normal(verts[0], verts[1], verts[2]);
 
-    // Emit main triangle
-    orientation = 0.0;
-    uv_coords = vec2(0.0);
-    emit_vertex_wrapper(verts[2], v_color[2], unit_normal);
-    emit_vertex_wrapper(v_base_point[0], v_color[1], unit_normal);
-    emit_vertex_wrapper(verts[0], v_color[0], unit_normal);
-
-    // Emit edge triangle
-    orientation = 1.0;
-    uv_coords = vec2(0, 0);
-    // Two dummies
-    emit_vertex_wrapper(verts[0], v_color[0], unit_normal);
-    emit_vertex_wrapper(verts[0], v_color[0], unit_normal);
-    // Inner corner
-    uv_coords = vec2(0.5, 0);
-    emit_vertex_wrapper(verts[1], v_color[1], unit_normal);
-    // Last corner
-    uv_coords = vec2(1.0, 1.0);
-    emit_vertex_wrapper(verts[2], v_color[2], unit_normal);
-    EndPrimitive();
+    if(int(v_inst_id[0]) % 2 == 0){
+        // Emit main triangle
+        fill_all = float(true);
+        uv_coords = vec2(0.0);
+        emit_vertex_wrapper(verts[0], v_color[0], unit_normal);
+        emit_vertex_wrapper(v_base_point[0], v_color[0], unit_normal);
+        emit_vertex_wrapper(verts[2], v_color[2], unit_normal);
+    }else{
+        // Emit edge triangle
+        fill_all = float(false);
+        uv_coords = vec2(0.0, 0.0);
+        emit_vertex_wrapper(verts[0], v_color[0], unit_normal);
+        uv_coords = vec2(0.5, 0);
+        emit_vertex_wrapper(verts[1], v_color[1], unit_normal);
+        uv_coords = vec2(1.0, 1.0);
+        emit_vertex_wrapper(verts[2], v_color[2], unit_normal);
+        EndPrimitive();
+    }
 }
 

manimlib/shaders/quadratic_bezier_fill/vert.glsl

@@ -9,10 +9,12 @@ out vec4 v_joint_product;
 out vec4 v_color;
 out vec3 v_base_point;
 out float v_vert_index;
+out float v_inst_id;
 
 void main(){
     verts = point;
     v_color = fill_rgba;
     v_base_point = base_point;
     v_vert_index = gl_VertexID;
+    v_inst_id = gl_InstanceID;
 }

manimlib/shaders/quadratic_bezier_stroke/geom.glsl

@@ -154,7 +154,7 @@ void main() {
     // actually only need every other strip element
     if (int(v_vert_index[0]) % 2 == 1) return;
 
-    // Curves are marked as eneded when the handle after
+    // Curves are marked as ended when the handle after
     // the first anchor is set equal to that anchor
     if (verts[0] == verts[1]) return;