Question

我在香椿着色器中有强度问题。强度值总是0但不应该是，我从顶点法线和光线方向计算它。我用过这个 reference card

vertexShader: 

varying vec2 vUv;
uniform vec3 ec_light_dir;
uniform mat3 normal_matrix;                   
varying float intensity;
attribute vec3 a_normal;
void main() {
    vec3 ec_normal = normalize(normal_matrix * a_normal);           
    intensity = dot(ec_light_dir,ec_normal);
    vUv = uv;
    gl_Position = projectionMatrix * modelViewMatrix * vec4( position, 1.0 );}


fragmentShader: 

uniform sampler2D tDiffuse;
varying vec2 vUv;

varying float intensity;

void main() {
    vec4 color = texture2D(tDiffuse, vUv);
    if (intensity > 0.95)   
        color = vec4(1.0,1.0,0.5,0.5);
    else if (intensity > 0.5)
        color = vec4(0.6,0.3,0.3,1.0);
    else if (intensity > 0.25)
        color = vec4(0.4,0.2,0.2,1.0);
    else
        color = vec4(0.2,0.1,0.1,1.0);
    gl_FragColor = color;
}

你告诉我我做错了吗？为什么强度始终为零？

Answer 1

确保this is my js page content form_value.js $(document).ready(function() { // Function to get input value. $('#text_value').click(function() { var text_value = $("#text").val(); if(text_value=='') { alert("Enter Some Text In Input Field"); }else{ alert(text_value); } }); // Funtion to get checked radio's value. $('#gender_value').click(function() { $('#result').empty(); var value = $("form input[type='gender']:checked").val(); if($("form input[type='gender']").is(':checked')) { $('#result').append("Checked Radio Button Value is :<span> "+ value +" </span>"); }else{ alert(" Please Select any Option "); } }); // Get value Onchange radio function. $('input:gender').change(function(){ var value = $("form input[type='gender']:checked").val(); alert("Value of Changed Radio is : " +value); }); // Funtion to reset or clear selection. $('#radio_reset').click(function() { $('#result').empty(); $("input:radio").attr("checked", false); }); $('#Email').click(function() { function validate(Email) { var reg = /^([A-Za-z0-9_\-\.])+\@([A-Za-z0-9_\-\.])+\.([A-Za- z]{2,4})$/; //var address = document.getElementById[email].value; if (reg.test(email) == false) { alert('Should be in the format example@gmail.com'); return (false); } } }); }); $("#Age").click(function() { var specialKeys = new Array(); specialKeys.push(8); //Backspace function IsNumeric(e) { var keyCode = e.which ? e.which : e.keyCode var ret = ((keyCode >= 48 && keyCode <= 57) || specialKeys.indexOf(keyCode) != -1); document.getElementById("error").style.display = ret ? "none" : "inline"; return ret; } function handleChange(input) { if (input.value < 0) input.value = 0; if (input.value > 100) input.value = 100; } }); </script>已标准化且a_normal不是零向量。为此，您可以将其值（每次运行一次）写入ec_light_dir并查看绘制的颜色。注意：将gl_FragColor传递给ec_light_dir不会确保它已标准化，因为如果其arg首先是零向量，则该函数具有未定义的行为。

GLSL香椿着色器中的零强度

1 个答案: