// Set either u_factor or v_factor to -1 (which negates the U- or v-values for the bumpmap) to see the problem            
#declare u_factor=-1;             
#declare v_factor=1;             
             

// rendered at 1223 by 697
camera {
  location <62.153965, 60.0, 249.138901>
  up <0.0, 1.0, 0.0>
 right <-1.754663, 0.0, 0.0>
  look_at <45.090450, 60.0, 150.605469>
  angle 72.019694
}

global_settings { ambient_light rgb<0.72, 0.72, 0.72> }

light_source { < -11.367086, 80.0, 16.717508 >, rgb <0.75, 0.75, 0.75>} 

#declare BUMP_MAT = texture { 
  pigment { color rgb<1.0, 0.976471, 0.854902>   }
  finish { ambient 0.8 diffuse 0.5 specular 0.3 roughness 0.12 reflection 0.0}
  normal { uv_mapping bump_map { jpeg "bump_pyramids.jpg" interpolate 2 use_color } bump_size 5.0 no_bump_scale }
}

mesh {

        triangle { 
                < -135.0, 97.125, 9.0 >,
                < 98.0, 97.125, 9.0 >,
                < 98.0, 0.0, 9.0 >
                uv_vectors <u_factor*8.4, v_factor*6.0> <u_factor*-6.1, v_factor*6.0> <u_factor*-6.1, v_factor*0.0>
                texture { BUMP_MAT }
        }
        triangle { 
                < -135.0, 97.125, 9.0 >, < 98.0, 0.0, 9.0 >, < -135.0, 0.0, 9.0 >
                
                uv_vectors <u_factor*8.4, v_factor*6.0> <u_factor*-6.1, v_factor*0.0> <u_factor*8.4, v_factor*0.0>
                
                texture { BUMP_MAT }
        }
}