glsl之纹理演示

前几章的shader有点问题，为什么在公司的机器上运行正常呢。

代码：http://download.csdn.net/detail/netrookie/4315735

vertex shader:

struct MaterialParameters 
{
   vec4 emission;
   vec4 ambient;
   vec4 diffuse;
   vec4 specular;
   float shininess;
};

struct LightSourceParameters 
{
   vec4 ambient;
   vec4 diffuse;
   vec4 specular;
   vec4 position;
   vec4 halfVector;
   vec3 spotDirection;
   float spotExponent;
   float spotCutoff;
   float spotCosCutoff;
   float constantAttenuation;
   float linearAttenuation;
   float quadraticAttenuation;
};

uniform mat4 m_mvp_mat;
uniform mat4 m_mv_mat;
uniform mat4 m_v_mat;
uniform mat4 m_model_it;

uniform MaterialParameters m_material_attr;
uniform LightSourceParameters m_light_attr;

attribute vec4 m_position;
attribute vec3 m_normal;
attribute vec2 a_texcoord;

varying vec4 ambient;
varying vec4 diffuse;

varying float dist;

varying vec3 normal, light_dir, half_vector;

varying float constantAttenuation, linearAttenuation, quadraticAttenuation;
varying vec4 light_specular, material_spcular;
varying float material_shininess;
varying vec3 spotDirection;
varying float spotExponent, spotCutoff, spotCosCutoff;
varying vec2 v_texcoord;

void main()
{
    vec3 position_mv, position_light;
    vec3 view_dir;
    vec3 aux;
    
    v_texcoord = a_texcoord;

    position_mv = vec3(m_mv_mat * m_position);
    
    /* light should not mul model matrix */
    position_light = vec3(m_v_mat * m_light_attr.position);

    aux = position_light - position_mv;
    light_dir = normalize(aux);
    dist = length(aux);

    normal = normalize(vec3(m_model_it * vec4(m_normal, 0.0)));

    view_dir = vec3(0.0, 0.0, 0.0) - position_mv;
    half_vector = normalize(view_dir - light_dir);

    ambient = m_material_attr.ambient * m_light_attr.ambient;
    diffuse = m_material_attr.diffuse * m_light_attr.diffuse;

    constantAttenuation = m_light_attr.constantAttenuation;
    linearAttenuation = m_light_attr.linearAttenuation;
    quadraticAttenuation = m_light_attr.quadraticAttenuation;

    light_specular = m_light_attr.specular;
    material_spcular = m_material_attr.specular;
    material_shininess = m_material_attr.shininess;

    spotDirection = m_light_attr.spotDirection;
    spotExponent = m_light_attr.spotExponent;
    spotCutoff = m_light_attr.spotCutoff;
    spotCosCutoff = m_light_attr.spotCosCutoff;

    gl_Position = m_mvp_mat * m_position;
}

frag shader:

uniform sampler2D texture1;

varying vec4 ambient;
varying vec4 diffuse;

varying float dist;

varying vec3 normal, light_dir, half_vector;

varying float constantAttenuation, linearAttenuation, quadraticAttenuation;
varying vec4 light_specular, material_spcular;
varying float material_shininess;
varying vec3 spotDirection;
varying float spotExponent, spotCutoff, spotCosCutoff;
varying vec2 v_texcoord;

void main(void)
{
   float n_dot_l, n_dot_hv;
   float att, spotEffect;
   vec4 color, specular, diffuse_;
   
   color = vec4(0.3, 0.3, 0.3, 1.0);
   
   /* normal and light_dir has normalized */
   n_dot_l = max(dot(normal, light_dir), 0.0);
   
   spotEffect = dot(normalize(spotDirection), normalize((-light_dir)));
  spotEffect = pow(spotEffect, spotExponent);

   if(n_dot_l > 0.0)
   {
      
      if(spotEffect > spotCosCutoff)
      {
            att = spotEffect / (constantAttenuation + 
      linearAttenuation * dist + 
      quadraticAttenuation * dist * dist);
      
      n_dot_hv = max(dot(normal, half_vector), 0.0);
      
      diffuse_ = n_dot_l * diffuse;
      
      specular = material_spcular * light_specular * pow(n_dot_hv, material_shininess); 
      
      color += att * (ambient + diffuse_ + specular);
      }
   }

   gl_FragColor = texture2D(texture1, v_texcoord) * color;
}

截图：