diff --git a/3d-viewer/3d_rendering/opengl/render_3d_opengl.cpp b/3d-viewer/3d_rendering/opengl/render_3d_opengl.cpp
index 822376de2d..220315b7cb 100644
--- a/3d-viewer/3d_rendering/opengl/render_3d_opengl.cpp
+++ b/3d-viewer/3d_rendering/opengl/render_3d_opengl.cpp
@@ -926,7 +926,7 @@ bool RENDER_3D_OPENGL::Redraw( bool aIsMoving, REPORTER* aStatusReporter,
     glTexEnvi( GL_TEXTURE_ENV, GL_SRC0_ALPHA, GL_PRIMARY_COLOR );
     glTexEnvi( GL_TEXTURE_ENV, GL_OPERAND0_ALPHA, GL_SRC_ALPHA );
     glTexEnvi( GL_TEXTURE_ENV, GL_SRC1_ALPHA, GL_CONSTANT );
-    glTexEnvi( GL_TEXTURE_ENV, GL_OPERAND1_ALPHA, GL_CONSTANT );
+    glTexEnvi( GL_TEXTURE_ENV, GL_OPERAND1_ALPHA, GL_SRC_ALPHA );
 
     render3dModels( false, true );
     render3dModels( true, true );