在OpenGL中显示两个不同的图像

Question

我最近刚开始研究OpenGL。当涉及到在具有两个不同纹理单位的单独对象中显示两个图像时，我需要帮助。第一个图像被渲染两次，而不是获得两个不同的图像。请问你认为可能出了什么问题？

int width, height, width1, height1;
unsigned char* image = SOIL_load_image("res/images/image1.jpg", &width, &height, 0, SOIL_LOAD_RGBA);
unsigned char* image1 = SOIL_load_image("res/images/image2.jpg", &width1, &height1, 0, SOIL_LOAD_RGBA);
GLuint texture, texture1;
//Texture0
glGenTextures(1, &texture);
glBindTexture(GL_TEXTURE_2D, texture);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, image);
glGenerateMipmap(GL_TEXTURE_2D);
SOIL_free_image_data(image);
glBindTexture(GL_TEXTURE_2D, 0);
//Texture 1
glGenTextures(1, &texture1);
glBindTexture(GL_TEXTURE_2D, texture1);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width1, height1, 0, GL_RGBA, GL_UNSIGNED_BYTE, image1);
glGenerateMipmap(GL_TEXTURE_2D);
SOIL_free_image_data(image1);
glBindTexture(GL_TEXTURE_2D, 0);

while (!glfwWindowShouldClose(window)) {
glfwPollEvents();
glViewport(0, 0, screenWidth, screenHeight);
glClearColor(0.2f, 0.3f, 0.3f, 1.0f);
glClear(GL_COLOR_BUFFER_BIT);
shader.Use();
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_2D, texture);
glUniform1i(glGetUniformLocation(shader.Program, "texture0"), 0);

glActiveTexture(GL_TEXTURE1);
glBindTexture(GL_TEXTURE_2D, texture1);
glUniform1i(glGetUniformLocation(shader.Program, "texture1"), 0); // the variable is the same with that of in core.frag
glBindVertexArray(VAO);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, EBO);
glDrawElements(GL_TRIANGLES, 12, GL_UNSIGNED_INT, 0);
glBindVertexArray(0);
glfwSwapBuffers(window);

Answer 1

绘制时使用两个不同的纹理单元，但绑定和加载两个纹理时使用相同的纹理单元。在绘制之前从中删除glActiveTexture(GL_TEXTURE1);，或者在第二次纹理加载之前使用glActiveTexture(GL_TEXTURE1);