Tech ENABLE_GL_SHADERS_ATTRIBUTES - Added shaders for glsl version 140

(cherry picked from commit prusa3d/PrusaSlicer@76d1d4949b)

resources/shaders/140/mm_gouraud.vs

@@ -0,0 +1,35 @@
+#version 140
+
+const vec3 ZERO = vec3(0.0, 0.0, 0.0);
+
+uniform mat4 view_model_matrix;
+uniform mat4 projection_matrix;
+
+uniform mat4 volume_world_matrix;
+// Clipping plane, x = min z, y = max z. Used by the FFF and SLA previews to clip with a top / bottom plane.
+uniform vec2 z_range;
+// Clipping plane - general orientation. Used by the SLA gizmo.
+uniform vec4 clipping_plane;
+
+in vec3 v_position;
+
+out vec3 clipping_planes_dots;
+out vec4 model_pos;
+out vec4 world_pos;
+struct SlopeDetection
+{
+    bool actived;
+	float normal_z;
+    mat3 volume_world_normal_matrix;
+};
+uniform SlopeDetection slope;
+void main()
+{
+    model_pos = vec4(v_position, 1.0);
+    // Point in homogenous coordinates.
+    world_pos = volume_world_matrix * model_pos;
+
+    gl_Position = projection_matrix * view_model_matrix * model_pos;
+    // Fill in the scalars for fragment shader clipping. Fragments with any of these components lower than zero are discarded.
+    clipping_planes_dots = vec3(dot(world_pos, clipping_plane), world_pos.z - z_range.x, z_range.y - world_pos.z);
+}