Some opengl additions

README.md

@@ -51,7 +51,7 @@ In `xdg-shell-protocol.cpp` - we need access to `xdg_wm_base_interface` so expor
 #### 3D Rendering
 
 ```bash
-sudo apt-get install libgl-dev libegl1-mesa-dev
+sudo apt-get install libgl-dev libegl1-mesa-dev libglu1-mesa-dev
 ```
 
 #### fonts

src/graphics/CMakeLists.txt

@@ -18,7 +18,7 @@ list(APPEND graphics_HEADERS
 set(OpenGL_GL_PREFERENCE "GLVND")
 find_package(OpenGL QUIET)
 if (OpenGL_FOUND)
-    list(APPEND platform_LIBS OpenGL::GL)
+    list(APPEND platform_LIBS OpenGL::GL OpenGL::GLU)
     list(APPEND graphics_LIB_INCLUDES opengl/OpenGlPainter.cpp)
     list(APPEND graphics_HEADERS opengl/OpenGlPainter.h)
 else()

src/graphics/opengl/OpenGlPainter.cpp

@@ -9,22 +9,129 @@
 #include <windows.h>
 #endif
 
+#define GL_GLEXT_PROTOTYPES
 #include <GL/gl.h>
+#include <GL/glu.h>
+#include <GL/glx.h>
 
 #include <iostream>
 
+const char* vertexShaderSource = "#version 330 core\n"
+    "layout (location = 0) in vec3 aPos;\n"
+    "void main()\n"
+    "{\n"
+    "   gl_Position = vec4(aPos.x, aPos.y, aPos.z, 1.0);\n"
+    "}\0";
+
+
+const char* fragmentShaderSource = "#version 330 core\n"
+        "out vec4 FragColor;\n"
+        "void main()\n"
+        "{\n"
+        "FragColor = vec4(1.0f, 0.5f, 0.2f, 1.0f);\n"
+        "}\n";
+
+
+OpenGlPainter::OpenGlPainter()
+{
+
+}
+
+void OpenGlPainter::initialize()
+{
+    if (auto context = glXGetCurrentContext())
+    {
+        std::cout << "has valid context" << std::endl;
+    }
+    else
+    {
+        std::cout << "no valid context" << std::endl;
+    }
+
+    int major_version{0};
+    int minor_version{0};
+    glGetIntegerv(GL_MAJOR_VERSION, &major_version);
+    glGetIntegerv(GL_MINOR_VERSION, &minor_version);
+    std::cout << "Using opengl version " << major_version << "|" << minor_version << std::endl;
+
+    std::cout << "Creating opengl painter" << std::endl;
+    unsigned int vertexShader = glCreateShader(GL_VERTEX_SHADER);
+    glShaderSource(vertexShader, 1, &vertexShaderSource, nullptr);
+    glCompileShader(vertexShader);
+
+    int  success;
+    char infoLog[512];
+    glGetShaderiv(vertexShader, GL_COMPILE_STATUS, &success);
+    if(!success)
+    {
+        glGetShaderInfoLog(vertexShader, 512, nullptr, infoLog);
+        std::cout << "ERROR::SHADER::VERTEX::COMPILATION_FAILED: " << std::string(infoLog) << std::endl;
+
+        if (auto errCode = glGetError(); errCode != GL_NO_ERROR)
+        {
+            auto errString = gluErrorString(errCode);
+            std::cout << "Got gl error" << errString << std::endl;
+        }
+    }
+    else
+    {
+        std::cout << "Shader compiled ok" << std::endl;
+        if (auto errCode = glGetError(); errCode != GL_NO_ERROR)
+        {
+            auto errString = gluErrorString(errCode);
+            std::cout << "Got gl error after ok" << errString << std::endl;
+        }
+    }
+
+    unsigned int fragmentShader;
+    fragmentShader = glCreateShader(GL_FRAGMENT_SHADER);
+    glShaderSource(fragmentShader, 1, &fragmentShaderSource, nullptr);
+    glCompileShader(fragmentShader);
+
+    glGetShaderiv(fragmentShader, GL_COMPILE_STATUS, &success);
+
+    if(!success)
+    {
+        glGetShaderInfoLog(fragmentShader, 512, NULL, infoLog);
+        std::cout << "ERROR::SHADER::FRAGMENT::COMPILATION_FAILED: " << infoLog << std::endl;
+    }
+
+    mShaderProgram = glCreateProgram();
+
+    glAttachShader(mShaderProgram, vertexShader);
+    glAttachShader(mShaderProgram, fragmentShader);
+    glLinkProgram(mShaderProgram);
+
+    glGetProgramiv(mShaderProgram, GL_LINK_STATUS, &success);
+    if(!success)
+    {
+        glGetProgramInfoLog(mShaderProgram, 512, NULL, infoLog);
+        std::cout << "Shader linking FAILED\n" << infoLog << std::endl;
+    }
+
+    glDeleteShader(vertexShader);
+    glDeleteShader(fragmentShader);
+
+    mInitialized = true;
+}
+
 void OpenGlPainter::paint(DrawingContext* context)
 {
+    if (!mInitialized)
+    {
+        initialize();
+    }
+
     auto surface = context->getSurface();
     const auto width = double(surface->getWidth());
     const auto height = double(surface->getHeight());
     const auto num_mesh = context->getScene()->getNumMeshes();
 
     glViewport(0, 0, width, height);
-    glOrtho(0, width, 0, height, -1.0, 1.0);
+    //glOrtho(-1.0, 1.0, -1.0, 1.0, -1.0, 1.0);
-    glScissor(0, 0, width, height);
+    //glScissor(0, 0, width, height);
-    glMatrixMode(GL_PROJECTION);
+    //glMatrixMode(GL_PROJECTION);
-    glLoadIdentity();
+    //glLoadIdentity();
 
     glClearColor(0.5, 0.5, 1.0, 0.0);
     glClear(GL_COLOR_BUFFER_BIT);
@@ -32,6 +139,30 @@ void OpenGlPainter::paint(DrawingContext* context)
     //glMatrixMode(GL_MODELVIEW);
    //glLoadIdentity();
 
+    float vertices[] = {
+        -0.5f, -0.5f, 0.0f,
+         0.5f, -0.5f, 0.0f,
+         0.0f,  0.5f, 0.0f
+    };
+    unsigned int vbo{0};
+    glGenBuffers(1, &vbo);
+
+    unsigned int VAO;
+    glGenVertexArrays(1, &VAO);
+    glBindVertexArray(VAO);
+
+    glBindBuffer(GL_ARRAY_BUFFER, vbo);
+    glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
+
+    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 3 * sizeof(float), (void*)0);
+    glEnableVertexAttribArray(0);
+
+    glUseProgram(mShaderProgram);
+    glBindVertexArray(VAO);
+
+    glDrawArrays(GL_TRIANGLES, 0, 3);
+
+    /*
     std::cout << "Bounds are : " << width << " | " << height << std::endl;
 
     for (std::size_t idx=0; idx<num_mesh; idx++)
@@ -50,14 +181,14 @@ void OpenGlPainter::paint(DrawingContext* context)
             glColor3f(r, g, b);
 
             glBegin(GL_TRIANGLES);
-            double x0 = face[0].getX();
+            double x0 = 2.0*face[0].getX()/width - 1.0;
-            double y0 = height -face[0].getY();
+            double y0 = 1.0 - 2.0*face[0].getY()/height;
 
-            double x1 = face[1].getX();
+            double x1 = 2.0*face[1].getX()/width - 1.0;
-            double y1 = height -face[1].getY();
+            double y1 = 1.0 - 2.0*face[1].getY()/height;
 
-            double x2 = face[2].getX();
+            double x2 = 2.0*face[2].getX()/width - 1.0;
-            double y2 = height -face[2].getY();
+            double y2 = 1.0 - 2.0*face[2].getY()/height;
 
             glVertex3f(x0, y0, 0);
             glVertex3f(x1, y1, 0);
@@ -71,8 +202,11 @@ void OpenGlPainter::paint(DrawingContext* context)
             glEnd();
 
             counter++;
+            break;
         }
+        break;
     }
+    */
 
     glFlush();
 }

src/graphics/opengl/OpenGlPainter.h

@@ -7,7 +7,16 @@ class DrawingContext;
 class OpenGlPainter : public AbstractPainter
 {
 public:
+
+    OpenGlPainter();
+
+
+    void initialize();
     void paint(DrawingContext* context) override;
+
+private:
+    bool mInitialized{false};
+    unsigned int mShaderProgram{0};
 };
 
 

src/windows/ui_interfaces/x11/XcbGlInterface.cpp

@@ -1,6 +1,7 @@
 #include "XcbGlInterface.h"
 
 #include "FileLogger.h"
+#include <iostream>
 
 #include <GL/gl.h>
 
@@ -59,6 +60,7 @@ void XcbGlInterface::setupContext(int default_screen)
     glXGetFBConfigAttrib(mDisplay, mConfig, GLX_VISUAL_ID, &visualID);
 
     /* Create OpenGL context */
+    std::cout << "Creating opengl context" << std::endl;
     mContext = glXCreateNewContext(mDisplay, mConfig, GLX_RGBA_TYPE, 0, True);
     if (!mContext)
     {

src/windows/ui_interfaces/x11/XcbGlWindowInterface.cpp

@@ -54,17 +54,18 @@ bool XcbGlWindowInterface::initialize(xcb_window_t window)
         MLOG_ERROR("glXMakeContextCurrent failed");
         return false;
     }
+
     return true;
 }
 
 void XcbGlWindowInterface::resizeViewPort(unsigned width, unsigned height)
 {
-    glViewport(0, 0, width, height);
+    //glViewport(0, 0, width, height);
-    glScissor(0, 0, width, height);
+    //glScissor(0, 0, width, height);
 
-    glOrtho(0, width, 0, height, -1.0, 1.0);
+    //glOrtho(0, width, 0, height, -1.0, 1.0);
-    glMatrixMode(GL_PROJECTION);
+    //glMatrixMode(GL_PROJECTION);
-    glLoadIdentity();
+    //glLoadIdentity();
 
     //glMatrixMode(GL_MODELVIEW);