Add texture displacement bump and UV-check shaders

resources/shaders/110/texture_displacement_uvcheck.vs

@@ -0,0 +1,31 @@
+#version 110
+
+// See resources/shaders/140/texture_displacement_uvcheck.vs; GLSL 1.10 compatibility variant.
+
+uniform mat4 view_model_matrix;
+uniform mat4 projection_matrix;
+uniform mat4 volume_world_matrix;
+uniform vec2 z_range;
+uniform vec4 clipping_plane;
+
+attribute vec3 v_position;
+attribute vec3 v_normal;    // .x = per-vertex uv distortion
+attribute vec2 v_tex_coord; // precomputed texture uv, used only when use_vertex_uv is set
+
+varying vec3  clipping_planes_dots;
+varying vec4  model_pos;
+varying vec4  world_pos;
+varying float distortion;
+varying vec2  vertex_uv;
+
+void main()
+{
+    model_pos = vec4(v_position, 1.0);
+    world_pos = volume_world_matrix * model_pos;
+
+    gl_Position = projection_matrix * view_model_matrix * model_pos;
+    clipping_planes_dots = vec3(dot(world_pos, clipping_plane), world_pos.z - z_range.x, z_range.y - world_pos.z);
+
+    distortion = v_normal.x;
+    vertex_uv  = v_tex_coord;
+}