尝试绑定纹理时GL_INVALID_OPERATION

Question

我的引擎中有多个纹理后遇到问题.

我的渲染代码目前看起来像这样:

void Renderer::render() {
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    checkGlError("glClear");

    for (vector<Node*>::const_iterator it = renderArray_.begin(); it != renderArray_.end();
            it++) {
        Node* node = *it;
        EntityModel* entity =
                static_cast<EntityModel*>(resourceManager_->getResource(
                        (*it)->getEntity()));
        if (entity == 0 || entity->getVertices() == 0 || entity->getVertices()->size() == 0) {
            LOGI("Empty entity %s.", node->getName().c_str());
            continue;
        }
        Resource* resource = resourceManager_->getResource(node->getShader());
        Shader* shader = static_cast<Shader*>(resource);
        Resource* resource2 = resourceManager_->getResource(entity->getTexture());
        Image* image = static_cast<Image*>(resource2);
        mat4 proj;
        Matrix::projection3D(proj, 45.0f,
                (float) nScreenWidth_ / nScreenHeight_, 0.1f, 100.0f);
        mat4 res;
        Matrix::multiply(proj, node->getMatrix(), res);

        // Select shader program to use.
        glUseProgram(shader->getId());
        checkGlError("glUseProgram");

        int matrix = glGetUniformLocation(shader->getId(), "uWVP");
        int texture = glGetUniformLocation(shader->getId(), "texture_0");
        checkGlError("glGetUniformLocation");
        int textureCoords = glGetAttribLocation(shader->getId(), "attrTexCoords");
        int vertices = glGetAttribLocation(shader->getId(), "attrPos");
        checkGlError("glGetAttribLocation");

        // Load vertex positions.
        glUniformMatrix4fv(matrix, 1, false, res);
        glVertexAttribPointer(vertices, 3, GL_FLOAT, GL_FALSE, 0,
                &(*entity->getVertices())[0]);
        glEnableVertexAttribArray(vertices);
        checkGlError("Loading vertex positions");

        glVertexAttribPointer(textureCoords, 2, GL_FLOAT, GL_FALSE, 0,
                &(*entity->getTextureCoords())[0]);
        checkGlError("glVertexAttribPointer");
        glEnableVertexAttribArray(textureCoords);
        checkGlError("glEnableVertexAttribArray");

        // Bind the texture.
        glActiveTexture(GL_TEXTURE0);
        checkGlError("glActiveTexture");
        glBindTexture(GL_TEXTURE_2D, image->getId());
        checkGlError("glBindTexture");
        glUniform1i(image->getId(), 0); <====================ERROR HERE!!!
        checkGlError("glUniform1i");

        glDrawArrays(GL_TRIANGLES, 0, entity->getVertices()->size() / 3);
        checkGlError("glDrawArrays");
    }
}

我的纹理加载代码:

void Image::compile() {
    glGenTextures(1, &id_);
    glBindTexture(GL_TEXTURE_2D, id_);
    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width_, height_, 0, GL_RGBA,
            GL_UNSIGNED_BYTE, (GLvoid*) image_);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
}

如果我只加载了一个纹理,一切正常.我有五个对象使用相同的纹理重复每个对象的渲染方法的内容,一切似乎运行正常.但是,就像我添加具有不同纹理的第六个对象一样,该对象不会被渲染,我继续在glUniform1i函数上获得GL_INVALID_OPERATION.我还检查了http://www.opengl.org/sdk/docs/man/xhtml/glUniform.xml的原因,为什么它不起作用,但似乎没有找到任何.

什么想法可能是错的？

Answer 1

这段代码

glUniform1i(image->getId(), 0);

反正是错的.您不会将纹理ID绑定到采样器,而是绑定到纹理单元.统一的第一个参数是位置ID,它也不是纹理ID.正确的代码看起来更像

glActiveTexture(GL_TEXTURE0 + active_textue);

/* ... */

glUniform1i(glGetUniformLocation(program, "samplername"), active_texture);

或者如果您在着色器中使用预定义位置

glUniform1i(texture_sample_location, active_texture);

编辑:噢,我身边的错误.当然,制服将偏移量赋予GL_TEXTURE0标记.