OpenGL均匀采样器2D具有相同的图像

Question

我无法通过统一的sampler2Ds将两个纹理发送到我的片段着色器。我的片段着色器有两个制服，但似乎我的代码将相同的图像发送给两个采样器。首先绑定的纹理似乎自动绑定到两个制服。

完整的C ++代码如下：

#define GLEW_STATIC
#include <GL/glew.h>
#include <GLFW/glfw3.h>
#include <glm/glm.hpp>
#include <glm/gtc/matrix_transform.hpp>
#include <glm/gtc/type_ptr.hpp>
#include <SOIL/SOIL.h>
#include <fstream>
#include <iostream>
#include <sstream>
#include <string>


int main(int argc, const char* argv[])
{
GLFWwindow* display;
glfwInit();

glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 4);
glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 0);
glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
glfwWindowHint(GLFW_OPENGL_FORWARD_COMPAT, GL_TRUE);
glfwWindowHint(GLFW_RESIZABLE, GL_TRUE);

display = glfwCreateWindow(1280, 720, "Game Engine", nullptr, nullptr);
glfwMakeContextCurrent(display);
glewExperimental = GL_TRUE;
GLenum success = glewInit();

GLint height, width;
glfwGetFramebufferSize(display, &width, &height);
glViewport(0, 0, width, height);
glEnable(GL_DEPTH_TEST);

GLuint program;
std::string vertexCode, fragmentCode;
std::ifstream vShaderFile, fShaderFile;

std::string vertexPath = "Basic.vert";
std::string fragmentPath = "Basic.frag";

vShaderFile.exceptions(std::ifstream::failbit | std::ifstream::badbit);
fShaderFile.exceptions(std::ifstream::failbit | std::ifstream::badbit);
try
{
    vShaderFile.open(vertexPath);
    fShaderFile.open(fragmentPath);
    std::stringstream vShaderStream, fShaderStream;

    vShaderStream << vShaderFile.rdbuf();
    fShaderStream << fShaderFile.rdbuf();

    vShaderFile.close();
    fShaderFile.close();

    vertexCode = vShaderStream.str();
    fragmentCode = fShaderStream.str();
}
catch(std::ifstream::failure error)
{
    std::cout << "Error: Shader file not successfully read." << std::endl;
}

GLuint vertex, fragment;
GLchar infoLog[512];

const GLchar* vertShaderCode = vertexCode.c_str();
vertex = glCreateShader(GL_VERTEX_SHADER);
glShaderSource(vertex, 1, &vertShaderCode, NULL);
glCompileShader(vertex);

const GLchar* fragShaderCode = fragmentCode.c_str();
fragment = glCreateShader(GL_FRAGMENT_SHADER);
glShaderSource(fragment, 1, &fragShaderCode, NULL);
glCompileShader(fragment);

program = glCreateProgram();
glAttachShader(program, vertex);
glAttachShader(program, fragment);
glLinkProgram(program);

glDeleteShader(vertex);
glDeleteShader(fragment);

GLfloat vertices[] = {
    -0.5f, -0.5f, -0.5f,  0.0f, 0.0f,
     0.5f, -0.5f, -0.5f,  1.0f, 0.0f,
     0.5f,  0.5f, -0.5f,  1.0f, 1.0f,
     0.5f,  0.5f, -0.5f,  1.0f, 1.0f,
    -0.5f,  0.5f, -0.5f,  0.0f, 1.0f,
    -0.5f, -0.5f, -0.5f,  0.0f, 0.0f,
};

GLuint VAO, VBO;
glGenVertexArrays(1, &VAO);
glGenBuffers(1, &VBO);
glBindVertexArray(VAO);
glBindBuffer(GL_ARRAY_BUFFER, VBO);
glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);

glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE,
                      5 * sizeof(GLfloat), (GLvoid*)0);
glEnableVertexAttribArray(0);

glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 5 * sizeof(GLfloat),
                      (GLvoid*)(3 * sizeof(GLfloat)));
glEnableVertexAttribArray(1);

GLuint texture0, texture1;

glGenTextures(1, &texture0);
glBindTexture(GL_TEXTURE_2D, texture0);
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);
unsigned char* image = SOIL_load_image("container.jpg",
    &width, &height, 0, SOIL_LOAD_RGB);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0,
    GL_RGB, GL_UNSIGNED_BYTE, image);
glGenerateMipmap(GL_TEXTURE_2D);
SOIL_free_image_data(image);
GLint uniform = glGetUniformLocation(program, "texture0");
glUniform1i(uniform, 0);

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);
image = SOIL_load_image("awesomeface.png",
    &width, &height, 0, SOIL_LOAD_RGB);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0,
    GL_RGB, GL_UNSIGNED_BYTE, image);
glGenerateMipmap(GL_TEXTURE_2D);
SOIL_free_image_data(image);
uniform = glGetUniformLocation(program, "texture1");
glUniform1i(uniform, 1);

glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_2D, texture0);
glActiveTexture(GL_TEXTURE1);
glBindTexture(GL_TEXTURE_2D, texture1);

while (!glfwWindowShouldClose(display))
{
    glClearColor(0.761f, 0.698f, 0.502f, 1.0f);
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    glUseProgram(program);

    glBindVertexArray(VAO);
    glDrawArrays(GL_TRIANGLES, 0, 6);

    glfwSwapBuffers(display);
    glfwPollEvents();
}

glDeleteVertexArrays(1, &VAO);
glDeleteBuffers(1, &VBO);

return EXIT_SUCCESS;
}

关联的GLSL着色器文件如下：顶点着色器：

#version 400 core
layout (location = 0) in vec3 position;
layout (location = 1) in vec2 texCoord;

out vec2 TexCoord;


void main()
{
gl_Position = vec4(position, 1.0f);
TexCoord = vec2(texCoord.x, 1.0 - texCoord.y);
}

片段着色器：

#version 400 core
in vec2 TexCoord;

out vec4 fragColor;

uniform sampler2D texture0;
uniform sampler2D texture1;


void main()
{
vec4 color1 = texture(texture0, TexCoord);
vec4 color2 = texture(texture1, TexCoord);
fragColor = mix(color1, color2, 0.4f);
}

Answer 1

另一答案