Fix broken coloring of wielditems (#9969)

Fixes a regression that appeared in 5.3.0-dev.

client/shaders/object_shader/opengl_fragment.glsl

@@ -145,6 +145,8 @@ void main(void)
 
 	vec4 col = vec4(color.rgb, base.a);
 
+	col.rgb *= gl_Color.rgb;
+
 	col.rgb *= emissiveColor.rgb * vIDiff;
 
 #ifdef ENABLE_TONE_MAPPING

client/shaders/object_shader/opengl_vertex.glsl

@@ -38,7 +38,12 @@ void main(void)
 
 	lightVec = sunPosition - worldPosition;
 	eyeVec = -(gl_ModelViewMatrix * gl_Vertex).xyz;
-	vIDiff = directional_ambient(normalize(gl_Normal));
+
+	// This is intentional comparison with zero without any margin.
+	// If normal is not equal to zero exactly, then we assume it's a valid, just not normalized vector
+	vIDiff = length(gl_Normal) == 0.0
+		? 1.0
+		: directional_ambient(normalize(gl_Normal));
 
 	gl_FrontColor = gl_BackColor = gl_Color;
 }

src/client/wieldmesh.cpp

@@ -467,6 +467,10 @@ void WieldMeshSceneNode::setColor(video::SColor c)
 			bc.getGreen() * green / 255,
 			bc.getBlue() * blue / 255);
 		scene::IMeshBuffer *buf = mesh->getMeshBuffer(j);
+
+		if (m_enable_shaders)
+			setMeshBufferColor(buf, buffercolor);
+		else
 			colorizeMeshBuffer(buf, &buffercolor);
 	}
 }
@@ -481,9 +485,9 @@ void WieldMeshSceneNode::setNodeLightColor(video::SColor color)
 			video::SMaterial &material = m_meshnode->getMaterial(i);
 			material.EmissiveColor = color;
 		}
-	} else {
-		setColor(color);
 	}
+
+	setColor(color);
 }
 
 void WieldMeshSceneNode::render()