# Extended PBR effect with support for additional texture types
# This effect supports metallic, emission, AO, detail, and gloss textures

fragment:
    defines: |
        #define USE_EXTENDED_TEXTURES 1

    inout: |
        uniform sampler2D p3d_Texture5;   // Metallic texture
        uniform sampler2D p3d_Texture6;   // Emission texture  
        uniform sampler2D p3d_Texture7;   // AO texture
        uniform sampler2D p3d_Texture8;   // Alpha texture
        uniform sampler2D p3d_Texture9;   // Detail texture
        uniform sampler2D p3d_Texture10;  // Gloss texture

    material: |
        #if USE_EXTENDED_TEXTURES
            
            // Metallic texture (p3d_Texture5)
            float sampled_metallic = texture(p3d_Texture5, texcoord).x;
            m.metallic = mInput.metallic * sampled_metallic;
            
            // Emission texture (p3d_Texture6)
            vec3 sampled_emission = texture(p3d_Texture6, texcoord).xyz;
            if (mInput.shading_model == SHADING_MODEL_EMISSIVE) {
                m.basecolor += sampled_emission * 2.0;  // Boost emission intensity
            }
            
            // AO texture (p3d_Texture7) - multiply with base color
            float sampled_ao = texture(p3d_Texture7, texcoord).x;
            m.basecolor *= sampled_ao;
            
            // Alpha texture (p3d_Texture8) - for transparency
            float sampled_alpha = texture(p3d_Texture8, texcoord).x;
            if (mInput.shading_model == SHADING_MODEL_TRANSPARENT) {
                // Apply alpha testing
                if (sampled_alpha < 0.5) discard;
            }
            
            // Detail texture (p3d_Texture9) - blend with base color
            vec3 sampled_detail = texture(p3d_Texture9, texcoord * 4.0).xyz;  // Tiled detail
            m.basecolor = mix(m.basecolor, m.basecolor * sampled_detail, 0.5);
            
            // Gloss texture (p3d_Texture10) - affects roughness
            float sampled_gloss = texture(p3d_Texture10, texcoord).x;
            m.roughness = m.roughness * (1.0 - sampled_gloss);  // Gloss is inverse of roughness
            
        #else
            // Standard behavior when extended textures are not used
            m.metallic = mInput.metallic;
        #endif