feat: add axes shaders and rendering functionality

CMakeLists.txt

@@ -94,6 +94,8 @@ target_link_libraries(OpenGLProject
 set(SHADER_FILES
         shaders/phong.vert
         shaders/phong.frag
+        shaders/axes.vert
+        shaders/axes.frag
 )
 
 # 将着色器文件复制到可执行文件旁边

main.cpp

@@ -21,15 +21,18 @@ int windowHeight = 768;
 
 // 着色器程序ID
 GLuint programID;
+GLuint axesProgramID; // Shader program for axes
 // GLuint pickingProgramID; // (可选，如果实现拾取)
 
 // Uniform ID
 GLuint MatrixID_MVP, MatrixID_M, MatrixID_V;
 GLuint LightPosID, LightColorID, LightPowerID, ViewPosID;
 GLuint TextureSamplerID;
+GLuint AxesMatrixID_MVP; // MVP uniform for axes shader
 
 // VAO 和 VBO
 GLuint CubeVAO, CubeVBO_vertices, CubeVBO_normals, CubeVBO_uvs;
+GLuint AxesVAO, AxesVBO_vertices, AxesVBO_colors;
 // GLuint LightVAO; // 用于表示光源的球体 (使用 GLUT 绘制，可能不需要单独VAO)
 
 // 纹理
@@ -40,7 +43,7 @@ glm::vec3 cameraPosition = glm::vec3(3.0f, 3.0f, 3.0f);
 float cameraHorizontalAngle = glm::pi<float>(); // 初始水平角 (pi)
 float cameraVerticalAngle = 0.0f;   // 初始垂直角
 float initialFoV = 45.0f;
-float cameraSpeed = 3.0f; // 单位/秒
+float cameraSpeed = 9.0f; // 单位/秒
 float mouseSpeed = 0.002f;
 
 // 鼠标状态
@@ -67,10 +70,11 @@ void mouseMotion(int x, int y);
 void idle();
 void createGradientTexture();
 void setupCubeBuffers();
+void setupAxesBuffers(); // Added
+void renderAxes(const glm::mat4& projectionMatrix, const glm::mat4& viewMatrix); // Added
 void renderText(const char* text, float x, float y, float r = 1.0f, float g = 1.0f, float b = 1.0f);
 
 // 立方体顶点数据 (位置, 法线, UV)
-// 36个顶点，因为每个面有不同法线或UV，不能共享顶点
 const GLfloat cube_vertices[] = {
     // Back face
     -0.5f, -0.5f, -0.5f,  // Bottom-left
@@ -116,6 +120,31 @@ const GLfloat cube_vertices[] = {
     -0.5f,  0.5f, -0.5f,  // top-left
 };
 
+// Axes vertex data
+const GLfloat axes_vertices[] = {
+    // X-axis (red)
+    0.0f, 0.0f, 0.0f,
+    2.0f, 0.0f, 0.0f,
+    // Y-axis (green)
+    0.0f, 0.0f, 0.0f,
+    0.0f, 2.0f, 0.0f,
+    // Z-axis (blue)
+    0.0f, 0.0f, 0.0f,
+    0.0f, 0.0f, 2.0f
+};
+
+const GLfloat axes_colors[] = {
+    // X-axis (red)
+    1.0f, 0.0f, 0.0f,
+    1.0f, 0.0f, 0.0f,
+    // Y-axis (green)
+    0.0f, 1.0f, 0.0f,
+    0.0f, 1.0f, 0.0f,
+    // Z-axis (blue)
+    0.0f, 0.0f, 1.0f,
+    0.0f, 0.0f, 1.0f
+};
+
 const GLfloat cube_normals[] = {
     // Back face
      0.0f,  0.0f, -1.0f,
@@ -273,6 +302,26 @@ void setupCubeBuffers() {
     glBindVertexArray(0);
 }
 
+void setupAxesBuffers() {
+    glGenVertexArrays(1, &AxesVAO);
+    glBindVertexArray(AxesVAO);
+
+    // Vertex positions
+    glGenBuffers(1, &AxesVBO_vertices);
+    glBindBuffer(GL_ARRAY_BUFFER, AxesVBO_vertices);
+    glBufferData(GL_ARRAY_BUFFER, sizeof(axes_vertices), axes_vertices, GL_STATIC_DRAW);
+    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 0, (void*)0);
+    glEnableVertexAttribArray(0);
+
+    // Vertex colors
+    glGenBuffers(1, &AxesVBO_colors);
+    glBindBuffer(GL_ARRAY_BUFFER, AxesVBO_colors);
+    glBufferData(GL_ARRAY_BUFFER, sizeof(axes_colors), axes_colors, GL_STATIC_DRAW);
+    glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 0, (void*)0);
+    glEnableVertexAttribArray(1);
+
+    glBindVertexArray(0);
+}
 
 void initGL() {
     glewExperimental = GL_TRUE;
@@ -302,6 +351,12 @@ void initGL() {
         exit(-1);
     }
 
+    axesProgramID = LoadShaders("shaders/axes.vert", "shaders/axes.frag");
+    if (axesProgramID == 0) {
+        std::cerr << "Failed to load axes shaders. Exiting." << std::endl;
+        exit(-1);
+    }
+
     // 添加着色器编译状态检查
     GLint success;
     GLchar infoLog[512];
@@ -329,8 +384,12 @@ void initGL() {
     TextureSamplerID = glGetUniformLocation(programID, "myTextureSampler");
     if (TextureSamplerID == -1) std::cerr << "myTextureSampler uniform not found" << std::endl;
 
+    AxesMatrixID_MVP = glGetUniformLocation(axesProgramID, "MVP");
+    if (AxesMatrixID_MVP == -1) std::cerr << "Axes MVP uniform not found" << std::endl;
+
     createGradientTexture();
     setupCubeBuffers();
+    setupAxesBuffers();
 
     glutSetCursor(GLUT_CURSOR_NONE);
     glutWarpPointer(windowWidth / 2, windowHeight / 2);
@@ -367,6 +426,23 @@ void renderText(const char* text, float x, float y, float r, float g, float b) {
     glPopMatrix();
 }
 
+void renderAxes(const glm::mat4& projectionMatrix, const glm::mat4& viewMatrix) {
+    glUseProgram(axesProgramID);
+
+    glm::mat4 ModelMatrixAxes = glm::mat4(1.0); // Identity matrix, axes at origin
+    glm::mat4 MVP_Axes = projectionMatrix * viewMatrix * ModelMatrixAxes;
+
+    if (AxesMatrixID_MVP != -1) {
+        glUniformMatrix4fv(AxesMatrixID_MVP, 1, GL_FALSE, &MVP_Axes[0][0]);
+    }
+
+    glBindVertexArray(AxesVAO);
+    glLineWidth(2.0f); // Make axes lines thicker
+    glDrawArrays(GL_LINES, 0, 6); // 3 lines, 2 vertices each
+    glBindVertexArray(0);
+    glLineWidth(1.0f); // Reset line width
+}
+
 void display() {
     // 检查OpenGL错误
     GLenum err;
@@ -383,17 +459,6 @@ void display() {
         std::cerr << "深度测试未启用" << std::endl;
     }
 
-    // 先绑定着色器程序
-    glUseProgram(programID);
-
-    // 检查着色器程序绑定状态
-    GLint currentProgram;
-    glGetIntegerv(GL_CURRENT_PROGRAM, &currentProgram);
-    if (currentProgram != programID) {
-        std::cerr << "着色器程序未正确绑定" << std::endl;
-        return;
-    }
-
     glm::vec3 direction(
         cos(cameraVerticalAngle) * sin(cameraHorizontalAngle),
         sin(cameraVerticalAngle),
@@ -413,6 +478,9 @@ void display() {
         up
     );
 
+    // Render Cube
+    glUseProgram(programID); // Ensure correct shader is used for the cube
+
     glm::mat4 ModelMatrixCube = glm::mat4(1.0);
     ModelMatrixCube = glm::translate(ModelMatrixCube, glm::vec3(0.0f, 0.0f, 0.0f));
     ModelMatrixCube = glm::rotate(ModelMatrixCube, cubeRotationAngle, glm::vec3(0.0f, 1.0f, 0.0f));
@@ -472,6 +540,9 @@ void display() {
     // 解绑VAO
     glBindVertexArray(0);
 
+    // Render Axes
+    renderAxes(ProjectionMatrix, ViewMatrix);
+
     // 检查绘制后的OpenGL错误
     while((err = glGetError()) != GL_NO_ERROR) {
         std::cerr << "OpenGL error after rendering: " << err << std::endl;
@@ -489,12 +560,12 @@ void display() {
     glutSolidSphere(0.1, 10, 10);
 
     // 渲染操作说明文字
-    renderText("操作说明:", 10, windowHeight - 20, 1.0f, 1.0f, 0.0f);
+    renderText("Controls:", 10, windowHeight - 20, 1.0f, 1.0f, 0.0f);
-    renderText("W/S: 前进/后退", 10, windowHeight - 40);
+    renderText("W/S: Move Forward/Backward", 10, windowHeight - 40);
-    renderText("A/D: 左移/右移", 10, windowHeight - 60);
+    renderText("A/D: Strafe Left/Right", 10, windowHeight - 60);
-    renderText("空格/C: 上升/下降", 10, windowHeight - 80);
+    renderText("Space/C: Move Up/Down", 10, windowHeight - 80);
-    renderText("鼠标左键拖拽: 视角旋转", 10, windowHeight - 100);
+    renderText("Left Mouse Drag: Rotate View", 10, windowHeight - 100);
-    renderText("ESC: 退出程序", 10, windowHeight - 120);
+    renderText("ESC: Exit Program", 10, windowHeight - 120);
 
     glutSwapBuffers();
 }
@@ -535,6 +606,11 @@ void keyboard(unsigned char key, int x, int y) {
         glDeleteVertexArrays(1, &CubeVAO);
         glDeleteProgram(programID);
         glDeleteTextures(1, &checkerboardTextureID);
+        // Cleanup for axes
+        glDeleteBuffers(1, &AxesVBO_vertices);
+        glDeleteBuffers(1, &AxesVBO_colors);
+        glDeleteVertexArrays(1, &AxesVAO);
+        glDeleteProgram(axesProgramID);
         exit(0);
         break;
     }
@@ -585,7 +661,6 @@ void mouseMotion(int x, int y) {
     }
 }
 
-
 void idle() {
     cubeRotationAngle += 0.005f;
     if (cubeRotationAngle > 2.0f * glm::pi<float>()) {

shader_utils.cpp

@@ -16,7 +16,6 @@ GLuint LoadShaders(const char * vertex_file_path, const char * fragment_file_pat
         sstr << VertexShaderStream.rdbuf();
         VertexShaderCode = sstr.str();
         VertexShaderStream.close();
-        std::cout << "顶点着色器代码:\n" << VertexShaderCode << std::endl;
     } else {
         std::cerr << "无法打开 " << vertex_file_path << ". 你是否在正确的目录下运行程序?" << std::endl;
         getchar();
@@ -31,7 +30,6 @@ GLuint LoadShaders(const char * vertex_file_path, const char * fragment_file_pat
         sstr << FragmentShaderStream.rdbuf();
         FragmentShaderCode = sstr.str();
         FragmentShaderStream.close();
-        std::cout << "片元着色器代码:\n" << FragmentShaderCode << std::endl;
     } else {
         std::cerr << "无法打开 " << fragment_file_path << ". 你是否在正确的目录下运行程序?" << std::endl;
         getchar();

shaders/axes.frag

@@ -0,0 +1,10 @@
+// shaders/axes.frag
+#version 330 core
+
+in vec3 fragmentColor;
+out vec3 color;
+
+void main(){
+    color = fragmentColor;
+}
+

shaders/axes.vert

@@ -0,0 +1,15 @@
+// shaders/axes.vert
+#version 330 core
+
+layout(location = 0) in vec3 vertexPosition_modelspace;
+layout(location = 1) in vec3 vertexColor;
+
+out vec3 fragmentColor;
+
+uniform mat4 MVP;
+
+void main(){
+    gl_Position = MVP * vec4(vertexPosition_modelspace, 1.0);
+    fragmentColor = vertexColor;
+}
+