[vert.glsl]
#version 130

in vec3 in_position;
in vec3 in_Normal;
in vec4 in_color;

uniform mat4 u_modelview;
uniform mat4 u_view;
uniform mat4 u_projection;
uniform mat3 u_normalmat;
uniform float u_damage;

out vec4 pass_vertex; /* View space */
out vec3 pass_tnormal;
out vec4 pass_color;

void main(void)
{
    vec4 vertex = vec4(in_position + (in_Normal * u_damage), 1.0);
    float dam_perc = u_damage / (0.1 * 40);
    vec3 vGravity = vec3(0.0, -0.981, 0.0) * 2.0;
    float k = pow(dam_perc, 3);
    vertex = u_modelview * vertex + u_view * vec4(vGravity * k, 1.0);
    vec3 tnorm = normalize(u_normalmat * in_Normal);

    pass_vertex = vertex;
    pass_tnormal = tnorm;
    pass_color = in_color;

    gl_Position = u_projection * vertex;
}

[frag.glsl]
#version 130

#if defined GL_ES
precision highp float;
#endif

in vec4 pass_vertex; /* View space */
in vec3 pass_tnormal;
in vec4 pass_color;

uniform mat4 u_view;
uniform mat4 u_inv_view;
uniform mat4 u_inv_modelview;
uniform float u_damage;

//Light list
uniform vec4 u_lights[8 * 2];

void main(void)
{
    /* Material properties */
    vec3 specular_reflect = vec3(0.8, 0.75, 0.4);
    float specular_power = 60.0;

    /* World properties */
    vec3 ambient = vec3(0.7, 0.7, 0.7);
    vec3 specular = vec3(0.0, 0.0, 0.0);
    vec3 diffuse = vec3(0.0, 0.0, 0.0);

    /* Light precalculations */
    vec3 v = normalize(-pass_vertex.xyz);

    /* Apply lighting */
    for (int i = 0; i < 8; i++)
    {
        vec4 pos = u_lights[i * 2];
        vec4 color = u_lights[i * 2 + 1];
        vec3 s, r;

        if (pos.w > 0.0)
        {
            /* Point light -- no attenuation yet */
            s = normalize((u_view * pos).xyz - pass_vertex.xyz);
            r = reflect(-s, pass_tnormal);
        }
        else
        {
            /* Directional light */
            s = normalize(-pos.xyz);
            r = reflect(s, pass_tnormal);
        }

        float sdotn = max(dot(s, pass_tnormal), 0.0);
        diffuse += color.xyz * sdotn;
        if (sdotn > 0.0)
            specular += color.xyz * specular_reflect
                         * pow(max(dot(r, v), 0.0), specular_power);
    }

    vec3 light = ambient + diffuse + specular;

    vec4 world_vertex = u_inv_modelview * pass_vertex;
    vec4 world_normal = u_inv_modelview * vec4(pass_tnormal, 1.0);

    float dam_perc = u_damage / (0.1 * 40);
    float PI = 3.14159265358979323846264;
    dam_perc = (sin(PI * (dam_perc - 0.5)) * 0.5 + 0.5);
    dam_perc *= dam_perc;
    dam_perc = 1.0 - dam_perc;
    float mod = 2.0;
    float transp = dam_perc;
                   /*
                   abs(sin(world_vertex.x * mod) * dam_perc * 0.5 + 0.5) *
                   abs(sin(world_vertex.y * mod) * dam_perc * 0.5 + 0.5) *
                   abs(sin(world_vertex.z * mod) * dam_perc * 0.5 + 0.5)
                   */

    //vec4 real_color = mix(pass_color, vec4(1.2, 1.2, 1.2, 1.0), u_damage);
    // - u_damage
    gl_FragColor = pass_color * vec4(light, (u_damage == 0)?(1.0):(transp));
}