opengl边框检测不完整

Question

opengl 用模板缓冲在做边框检测出现边框不完整的情况请问该如何进行处理?

看了 https://learnopengl-cn.github.io/04%20Advanced%20OpenGL/02%20Stencil%20testing/
教程中说的，但是依旧没有找到解决办法。

代码：

  // 深度测试、模板测试
  glEnable(GL_DEPTH_TEST);
  // 当前片段值小于缓冲深度值
  glDepthFunc(GL_LESS);
  // 开启模板测试
  glEnable(GL_STENCIL_TEST);
  // 绘制箱子上模板值不为1的部分
  glStencilFunc(GL_NOTEQUAL, 1, 0xFF);
  // 片段通过测试该如何操作
  glStencilOp(GL_KEEP, GL_KEEP, GL_REPLACE);

/////////////渲染循环内/////////////////////////////////////
  while (!glfwWindowShouldClose(window))
  {
    float currentFrame = static_cast<float>(glfwGetTime());
    deltaTime = currentFrame - lastFrame;
    lastFrame = currentFrame;

    processInput(window);

    glClearColor(0.1f, 0.1f, 0.1f, 1.0f);
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT); 

    shaderSingleColor.use();
    glm::mat4 model = glm::mat4(1.0f);
    glm::mat4 view = camera.GetViewMatrix();
    glm::mat4 projection = glm::perspective(glm::radians(camera.Zoom), (float)SCR_WIDTH / (float)SCR_HEIGHT, 0.1f, 100.0f);
    shaderSingleColor.setMat4("view", view);
    shaderSingleColor.setMat4("projection", projection);

    shader.use();
    shader.setMat4("view", view);
    shader.setMat4("projection", projection);

    // 先将所有的都设置为0 因为我不想让所有的都产生线框（此处为对面禁用）
    glStencilMask(0x00); // 禁用写入

    glBindVertexArray(planeVAO);
    glBindTexture(GL_TEXTURE_2D, floorTexture);
    shader.setMat4("model", glm::mat4(1.0f));
    glDrawArrays(GL_TRIANGLES, 0, 6);
    glBindVertexArray(0);

    // 此处让模型具有线框
    glStencilFunc(GL_ALWAYS, 1, 0xFF);
    glStencilMask(0xFF);

    glBindVertexArray(cubeVAO);
    // 激活给定的纹理单元
    glActiveTexture(GL_TEXTURE0);
    glBindTexture(GL_TEXTURE_2D, cubeTexture);
    model = glm::translate(model, glm::vec3(-1.0f, 0.0f, -1.0f));
    shader.setMat4("model", model);
    glDrawArrays(GL_TRIANGLES, 0, 36);
    
    model = glm::mat4(1.0f);
    model = glm::translate(model, glm::vec3(2.0f, 0.0f, 0.0f));
    shader.setMat4("model", model);
    glDrawArrays(GL_TRIANGLES, 0, 36);

    glStencilFunc(GL_NOTEQUAL, 1, 0xFF);
    glStencilMask(0xFF);

    // 禁用深度测试 不会被地板覆盖
    glDisable(GL_DEPTH_TEST);
    shaderSingleColor.use();
    float scale = 1.01f;
    // cubes
    glBindVertexArray(cubeVAO);
    glBindTexture(GL_TEXTURE_2D, cubeTexture);
    model = glm::mat4(1.0f);
    model = glm::translate(model, glm::vec3(-1.0f, 0.0f, -1.0f));
    model = glm::scale(model, glm::vec3(scale, scale, scale));
    shaderSingleColor.setMat4("model", model);
    glDrawArrays(GL_TRIANGLES, 0, 36);
    
    /* 不显示线框 */
    //glStencilFunc(GL_NOTEQUAL, 1, 0x00);
    //glStencilMask(0x00);

    model = glm::mat4(1.0f);
    model = glm::translate(model, glm::vec3(2.0f, 0.0f, 0.0f));
    model = glm::scale(model, glm::vec3(scale, scale, scale));
    shaderSingleColor.setMat4("model", model);
    glDrawArrays(GL_TRIANGLES, 0, 36);
    glBindVertexArray(0);

    glStencilMask(0xFF);
    glStencilFunc(GL_ALWAYS, 0, 0xFF);
    glEnable(GL_DEPTH_TEST);

    glfwSwapBuffers(window);
    glfwPollEvents();
  }

Answer 1

已解决，上面的实现是，先一起绘制两个cube实体，在进行绘制两个边框cube，最终所产生的效果就是两个边框是链接的。要想绘制完整的边框需要，绘制一个实体在绘制一个边框，之后清除模板缓冲，这样依次绘制问题就解决了。