Yo talented fellas!
I hope you can help me : )
I using Nanogui and NanoVG for my application. There I have inherited the screen for my viewport object and have implemented the virtual draw functions.
Everything seems to work nice in my demo application like this.
namespace sintonic {
// Default constructor
Viewport::Viewport(const Vector2i size, const std::string caption, bool resize, bool fullscreen) : Screen(size, caption, resize, fullscreen) {
};
void Viewport::drawAll() {
glClearColor(mBackground[0], mBackground[1], mBackground[2], 1.0f);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
initGL();
drawContents();
drawWidgets();
glfwSwapBuffers(mGLFWWindow);
}
void Viewport::drawContents() {
glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0);
}
void Viewport::initGL() {
// Temporary triangle for GL
GLfloat vertices[] = {
0.5f, 0.5f, 0.0f, // Top Right
0.5f, -0.5f, 0.0f, // Bottom Right
-0.5f, -0.5f, 0.0f, // Bottom Left
-0.5f, 0.5f, 0.0f // Top Left
};
GLuint indices[] = { // Note that we start from 0!
0, 1, 3, // First Triangle
1, 2, 3 // Second Triangle
};
// Build and compile our shader program
// Vertex shader
GLuint vertexShader = glCreateShader(GL_VERTEX_SHADER);
glShaderSource(vertexShader, 1, &vertexShaderSource, NULL);
glCompileShader(vertexShader);
// Check for compile time errors
GLint success;
GLchar infoLog[512];
glGetShaderiv(vertexShader, GL_COMPILE_STATUS, &success);
if (!success)
{
glGetShaderInfoLog(vertexShader, 512, NULL, infoLog);
std::cout << "ERROR::SHADER::VERTEX::COMPILATION_FAILED
" << infoLog << std::endl;
}
// Fragment shader
GLuint fragmentShader = glCreateShader(GL_FRAGMENT_SHADER);
glShaderSource(fragmentShader, 1, &fragmentShaderSource, NULL);
glCompileShader(fragmentShader);
// Check for compile time errors
glGetShaderiv(fragmentShader, GL_COMPILE_STATUS, &success);
if (!success)
{
glGetShaderInfoLog(fragmentShader, 512, NULL, infoLog);
std::cout << "ERROR::SHADER::FRAGMENT::COMPILATION_FAILED
" << infoLog << std::endl;
}
// Link shaders
GLuint shaderProgram = glCreateProgram();
glAttachShader(shaderProgram, vertexShader);
glAttachShader(shaderProgram, fragmentShader);
glLinkProgram(shaderProgram);
// Check for linking errors
glGetProgramiv(shaderProgram, GL_LINK_STATUS, &success);
if (!success) {
glGetProgramInfoLog(shaderProgram, 512, NULL, infoLog);
std::cout << "ERROR::SHADER::PROGRAM::LINKING_FAILED
" << infoLog << std::endl;
}
GLuint VBO, VAO, EBO;
glGenVertexArrays(1, &VAO);
glGenBuffers(1, &VBO);
glGenBuffers(1, &EBO);
// Bind the Vertex Array Object first, then bind and set vertex buffer(s) and attribute pointer(s).
glBindVertexArray(VAO);
glBindBuffer(GL_ARRAY_BUFFER, VBO);
glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, EBO);
glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(indices), indices, GL_STATIC_DRAW);
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 3 * sizeof(GLfloat), (GLvoid*)0);
glEnableVertexAttribArray(0);
glBindBuffer(GL_ARRAY_BUFFER, 0); // Note that this is allowed, the call to glVertexAttribPointer registered VBO as the currently bound vertex buffer object so afterwards we can safely unbind
glBindVertexArray(0); // Unbind VAO (it's always a good thing to unbind any buffer/array to prevent strange bugs), remember: do NOT unbind the EBO, keep it bound to this VAO
// Draw our first triangle
glUseProgram(shaderProgram);
glBindVertexArray(VAO);
}
}
However! If I change my initGL() to the class constructor I get Error 00000502 after convex fill ?
Like this.
// Default constructor
Viewport::Viewport(const Vector2i size, const std::string caption, bool resize, bool fullscreen) : Screen(size, caption, resize, fullscreen) {
initGL();
};
I would like to init the buffers only once and then simply draw them every frame. How could I acheve that and what I`m doing wrong? Uhh…
I bet I`m doing stupid things but please sensei help me!! : )
Thanks,
- J