我想将多个纹理发送到片段着色器，然后将它们混合在一起。 但是由于某种原因，当我运行这段代码时，只显示 texture2。即使我只写 color=color1;，在我的片段着色器中也是如此。比我还看到 texure2。
我的片段着色器:
static const char* fragmentShaderSource = "\n\
#version 150 core\n\
in vec2 Texcoord;\n\
uniform sampler2D tex0;\n\
uniform sampler2D tex1;\n\
out vec4 color;\n\
void main(){\n\
vec4 color1=texture(tex0,Texcoord);\n\
vec4 color2=texture(tex1,Texcoord);\n\
color=mix(color1,color2,0.5);\n\
//color=color1;\n\
}\n\
";
我的多重纹理代码:
GLuint textures[2];
glGenTextures(2, textures);
int width, height;
unsigned char* image;
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE0, textures[0]);
image = SOIL_load_image("1.png", &width, &height, 0, SOIL_LOAD_RGBA);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, image);
glGenerateMipmap(GL_TEXTURE_2D);
glUniform1i(glGetUniformLocation(program, "tex0"), 0);
SOIL_free_image_data(image);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glActiveTexture(GL_TEXTURE1);
glBindTexture(GL_TEXTURE1, textures[1]);
image = SOIL_load_image("2.png", &width, &height, 0, SOIL_LOAD_RGBA);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, image);
glGenerateMipmap(GL_TEXTURE_2D);
glUniform1i(glGetUniformLocation(program, "tex1"), 1);
SOIL_free_image_data(image);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
这是我的窗口循环:
while (!glfwWindowShouldClose(window)) {
glClearColor(1.0f, 1.0f, 1.0f, 1.0f);
glClear(GL_COLOR_BUFFER_BIT);
glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0);
if (glfwGetKey(window, GLFW_KEY_E)) {
break;
}
glfwSwapBuffers(window);
glfwPollEvents();
}
如果需要，这是我的全部代码:
#define GLEW_STATIC
#include<gl\glew.h>
#include<GLFW\glfw3.h>
#include<iostream>
#include<SOIL.h>
//////////////////////////////////////
static const char* vertexShaderSource = "\n\
#version 150 core\n\
in vec2 position;\n\
in vec3 inColor;\n\
in vec2 texcoord;\n\
out vec2 Texcoord;\n\
out vec3 Color;
void main(){\n\
Color=inColor;\n\
Texcoord=texcoord;\n\
gl_Position=vec4(position,0,1);\n\
}\n";
static const char* fragmentShaderSource = "\n\
#version 150 core\n\
//uniform vec4 fragmentColor;\n\
in vec3 Color;\n\
in vec2 Texcoord;\n\
uniform sampler2D tex0;\n\
uniform sampler2D tex1;\n\
out vec4 color;\n\
void main(){\n\
vec4 color1=texture(tex0,Texcoord);\n\
vec4 color2=texture(tex1,Texcoord);\n\
color=mix(color1,color2,0.5);\n\
//color=color1;\n\
}\n\
";
//////////////////////////////////////
int main() {
if (!glfwInit())
return -1;
glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 2);
glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
glfwWindowHint(GLFW_OPENGL_FORWARD_COMPAT, GL_TRUE);
GLFWwindow* window = glfwCreateWindow(1024, 620, "Window", nullptr, nullptr);
glfwMakeContextCurrent(window);
glewExperimental = GL_TRUE;
if (glewInit() != GLEW_OK)
return -1;
GLfloat triangleVertices[] = {
0.5f,0.5f,1,0,0,1,0,
0.5f,-0.5f,0,1,0,1,1,
-0.5f,-0.5f,0,0,1,0,1,
-0.5f,0.5f,0,0,0,0,0
};
GLuint vao;
glGenVertexArrays(1, &vao);
glBindVertexArray(vao);
GLuint vbo;
glGenBuffers(1, &vbo);
glBindBuffer(GL_ARRAY_BUFFER, vbo);
glBufferData(GL_ARRAY_BUFFER, sizeof(triangleVertices), triangleVertices, GL_STATIC_DRAW);
GLuint elements[] = { 0,1,2 ,3,0,2};
GLuint ebo;
glGenBuffers(1, &ebo);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, ebo);
glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(elements), elements, GL_STATIC_DRAW);
////////////////////////////////////////////////////////
GLuint vertexShader = glCreateShader(GL_VERTEX_SHADER);
glShaderSource(vertexShader, 1, &vertexShaderSource, nullptr);
glCompileShader(vertexShader);
GLint statusVertex;
glGetShaderiv(vertexShader, GL_COMPILE_STATUS, &statusVertex);
if (!statusVertex) {
char buffer[1024];
glGetShaderInfoLog(vertexShader, 1024, NULL, buffer);
std::cout << "Error Compiling vertexShader:" << buffer << std::endl;
}
GLuint fragmentShader = glCreateShader(GL_FRAGMENT_SHADER);
glShaderSource(fragmentShader, 1, &fragmentShaderSource, nullptr);
glCompileShader(fragmentShader);
GLint statusFrag;
glGetShaderiv(vertexShader, GL_COMPILE_STATUS, &statusFrag);
if (!statusFrag) {
char buffer[1024];
glGetShaderInfoLog(fragmentShader, 1024, NULL, buffer);
std::cout << "Error Compiling fragmentShader:" << buffer << std::endl;
}
GLuint program = glCreateProgram();
glAttachShader(program, vertexShader);
glAttachShader(program, fragmentShader);
glBindFragDataLocation(program, 0, "color");
glLinkProgram(program);//making connection
glUseProgram(program);
//////////////////////////////////////////////////////////
GLint positionAttrib = glGetAttribLocation(program, "position");
glVertexAttribPointer(positionAttrib, 2, GL_FLOAT, GL_FALSE, 7 * sizeof(GL_FLOAT), nullptr);
glEnableVertexAttribArray(positionAttrib);
GLint colorAttrib = glGetAttribLocation(program, "inColor");
glVertexAttribPointer(colorAttrib, 3, GL_FLOAT, GL_FALSE, 7 * sizeof(GL_FLOAT), (void*)(2 * sizeof(GL_FLOAT)));
glEnableVertexAttribArray(colorAttrib);
GLint texAttrib = glGetAttribLocation(program, "texcoord");
glVertexAttribPointer(texAttrib, 3, GL_FLOAT, GL_FALSE, 7 * sizeof(GL_FLOAT), (void*)(5 * sizeof(GL_FLOAT)));
glEnableVertexAttribArray(texAttrib);
GLuint textures[2];
glGenTextures(2, textures);
int width, height;
unsigned char* image;
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE0, textures[0]);
image = SOIL_load_image("1.png", &width, &height, 0, SOIL_LOAD_RGBA);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, image);
glGenerateMipmap(GL_TEXTURE_2D);
glUniform1i(glGetUniformLocation(program, "tex0"), 0);
SOIL_free_image_data(image);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glActiveTexture(GL_TEXTURE1);
glBindTexture(GL_TEXTURE1, textures[1]);
image = SOIL_load_image("2.png", &width, &height, 0, SOIL_LOAD_RGBA);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, image);
glGenerateMipmap(GL_TEXTURE_2D);
glUniform1i(glGetUniformLocation(program, "tex1"), 1);
SOIL_free_image_data(image);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
/////////////////////////////////////////////////////////////
while (!glfwWindowShouldClose(window)) {
glClearColor(1.0f, 1.0f, 1.0f, 1.0f);
glClear(GL_COLOR_BUFFER_BIT);
//glDrawArrays(GL_TRIANGLES, 0, 3);
glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0);
if (glfwGetKey(window, GLFW_KEY_E)) {
break;
}
glfwSwapBuffers(window);
glfwPollEvents();
}
glfwDestroyWindow(window);
glfwTerminate();
return 0;
}
最佳答案
glBindTexture 采用纹理目标 而不是单位。
目标是:GL_TEXTURE_1D、GL_TEXTURE_2D、GL_TEXTURE_3D、GL_TEXTURE_CUBE_MAP、GL_TEXTURE_1D_ARRAY、GL_TEXTURE_2D_ARRAY(和扩展特定目标)。
纹理 unit 被传递给 glActiveTexture，它们是 GL_TEXTURE0、GL_TEXTURE1 等等，也是采样器统一设置的内容。
将您的代码更改为
glActiveTexture(GL_TEXTURE0);
--- glBindTexture(GL_TEXTURE_2D, textures[0]);
+++ glBindTexture(GL_TEXTURE_2D, textures[0]);
和
glActiveTexture(GL_TEXTURE1);
--- glBindTexture(GL_TEXTURE_2D, textures[1]);
+++ glBindTexture(GL_TEXTURE_2D, textures[1]);
关于c++ - 如何解决 Opengl 中多个纹理的这个问题，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/58426191/