replace gl_PerVertex

GLMakie/assets/shader/sprites.geom

@@ -7,13 +7,6 @@
 struct Nothing{ bool _; };
 
 layout(points) in;
-// Need to set size of ClipDistance
-in gl_PerVertex {
-    vec4 gl_Position;
-    float gl_PointSize;
-    float gl_ClipDistance[8];
-} gl_in[];
-
 layout(triangle_strip, max_vertices = 4) out;
 
 mat4 qmat(vec4 quat){
@@ -56,6 +49,7 @@ in vec3 g_position[];
 in vec4 g_rotation[];
 in vec4 g_offset_width[];
 in uvec2 g_id[];
+in float g_clip_distance[][8];
 
 flat out int  f_primitive_index;
 flat out float f_viewport_from_u_scale;
@@ -98,7 +92,7 @@ void emit_vertex(vec4 vertex, vec2 uv)
     f_id              = g_id[0];
     f_sprite_scale    = g_offset_width[0].zw;
     for (int i = 0; i < 8; i++)
-        gl_ClipDistance[i] = gl_in[0].gl_ClipDistance[i];
+        gl_ClipDistance[i] = g_clip_distance[0][i];
     EmitVertex();
 }
 

GLMakie/assets/shader/sprites.vert

@@ -87,18 +87,33 @@ out vec4  g_rotation;
 out vec4  g_color;
 out vec4  g_stroke_color;
 out vec4  g_glow_color;
+out float g_clip_distance[8];
 
 vec4 to_vec4(vec3 x){return vec4(x, 1.0);}
 vec4 to_vec4(vec4 x){return x;}
-void process_clip_planes(vec3 world_pos);
+
+uniform int num_clip_planes;
+uniform vec4 clip_planes[8];
+
+void process_clip_planes_alt(vec3 world_pos)
+{
+    // distance = dot(world_pos - plane.point, plane.normal)
+    // precalculated: dot(plane.point, plane.normal) -> plane.w
+    for (int i = 0; i < num_clip_planes; i++)
+        g_clip_distance[i] = dot(world_pos, clip_planes[i].xyz) - clip_planes[i].w;
+
+    // TODO: can be skipped?
+    for (int i = num_clip_planes; i < 8; i++)
+        g_clip_distance[i] = 1.0;
+}
 
 void main(){
     int index         = gl_VertexID;
     g_primitive_index = index;
     vec3 pos;
     {{position_calc}}
     vec4 world_pos = model * vec4(pos, 1);
-    process_clip_planes(world_pos.xyz);
+    process_clip_planes_alt(world_pos.xyz);
     vec4 p = preprojection * world_pos;
     if (scale_primitive)
         g_position = p.xyz / p.w + mat3(model) * marker_offset;