1 files changed, 43 insertions, 0 deletions
diff --git a/source/blender/draw/engines/overlay/shaders/overlay_grid_vert.glsl b/source/blender/draw/engines/overlay/shaders/overlay_grid_vert.glsl
new file mode 100644
index 00000000000..b43b1eb4a52
--- /dev/null
+++ b/source/blender/draw/engines/overlay/shaders/overlay_grid_vert.glsl
@@ -0,0 +1,43 @@
+/**
+ * Infinite grid:
+ * Draw antialiazed grid and axes of different sizes with smooth blending between Level of details.
+ * We draw multiple triangles to avoid float precision issues due to perspective interpolation.
+ **/
+
+#pragma BLENDER_REQUIRE(common_view_lib.glsl)
+#pragma BLENDER_REQUIRE(common_math_lib.glsl)
+
+void main()
+{
+  vec3 vert_pos;
+
+  /* Project camera pos to the needed plane */
+  if (flag_test(grid_flag, PLANE_XY)) {
+    vert_pos = vec3(pos.x, pos.y, 0.0);
+  }
+  else if (flag_test(grid_flag, PLANE_XZ)) {
+    vert_pos = vec3(pos.x, 0.0, pos.y);
+  }
+  else if (flag_test(grid_flag, PLANE_YZ)) {
+    vert_pos = vec3(0.0, pos.x, pos.y);
+  }
+  else /* PLANE_IMAGE */ {
+    vert_pos = vec3(pos.xy * 0.5 + 0.5, 0.0);
+  }
+
+  local_pos = vert_pos;
+
+  vec3 real_pos = cameraPos * plane_axes + vert_pos * grid_buf.size.xyz;
+
+  /* Used for additional Z axis */
+  if (flag_test(grid_flag, CLIP_ZPOS)) {
+    real_pos.z = clamp(real_pos.z, 0.0, 1e30);
+    local_pos.z = clamp(local_pos.z, 0.0, 1.0);
+  }
+  if (flag_test(grid_flag, CLIP_ZNEG)) {
+    real_pos.z = clamp(real_pos.z, -1e30, 0.0);
+    local_pos.z = clamp(local_pos.z, -1.0, 0.0);
+  }
+
+  gl_Position = drw_view.persmat * vec4(real_pos, 1.0);
+}