c++ - OpenGLESv2 着色器 glGetAttribLocation 返回 -1

Question

嘿，我尝试编写 OpenGL ES 2 引擎代码，但在创建着色器时，函数 glGetAttribLocation 返回 -1，这意味着

The named attribute variable is not an active attribute in the specified program object or the name starts with the reserved prefix "gl_".

但它是在着色器中定义的并且不是以 gl_ 开头的。 我的代码有什么问题？

C++代码:

glprogram = glCreateProgram();

glvertshader = glCreateShader(GL_VERTEX_SHADER);
glfragshader = glCreateShader(GL_FRAGMENT_SHADER);

glShaderSource(glvertshader, 1, vertsrc, NULL);
glShaderSource(glfragshader, 1, fragsrc, NULL);

GLint ret;

glCompileShader(glvertshader);
glGetShaderiv(glvertshader, GL_COMPILE_STATUS, &ret);
if(!ret)
{
    ///error handling - stripped for the internet
}

glCompileShader(glfragshader);
glGetShaderiv(glfragshader, GL_COMPILE_STATUS, &ret);
if(!ret)
{
    ///error handling - stripped for the internet
}

glAttachShader(glprogram, glvertshader);
glAttachShader(glprogram, glfragshader);

glLinkProgram(glprogram);

glGetProgramiv(glprogram, GL_LINK_STATUS, &ret);
if(!ret)
{
    ///error handling - stripped for the internet
}

glattributes[0] = glGetAttribLocation(glprogram, "vertex");
glattributes[1] = glGetAttribLocation(glprogram, "texcoord_vs");



std::cout << "texcoord " << glGetAttribLocation(glprogram, "texcoord_vs";

垂直着色器:

// Vertex Shader for OpenGL ES
uniform mat4 projmat;
uniform mat4 modviewmat;

attribute vec2 vertex;
attribute vec2 texcoord_vs;

varying vec2 texcoord_fs;

void main()
{
    texcoord_fs = texcoord_vs;
    gl_Position = projmat*modviewmat*vec4(vertex, 0.0, 1.0);
}

编辑:更正着色器代码，错误与 texcoord_vs 有关。

Answer 1

您没有指定未使用哪个属性，但我假设它是“texcoord_vs”，只是因为您没有使用它，因此它被着色器编译器剥离。

我想你的意思是 texcoord_fs = texcoord_vs？