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#include "glad/glad.h"
#include "GLFW/glfw3.h"
#include "input.hpp"
#include "shader.hpp"
#define STB_IMAGE_IMPLEMENTATION
#include "stb_image.h"
#include <iostream>
#include <cmath>
//#include <unistd.h> // use to print working directory
//#include <stdio.h>
float vertices[] = {
// positions // colors // texture coords
0.5f, 0.5f, 0.0f, 0.0f, 0.0f, 1.0f, 1.0f, 1.0f, // top right
0.5f, -0.5f, 0.0f, 1.0f, 0.0f, 0.0f, 1.0f, 0.0f, // bottom right
-0.5f, -0.5f, 0.0f, 0.0f, 1.0f, 0.0f, 0.0f, 0.0f, // bottom left
-0.5f, 0.5f, 0.0f, 1.0f, 1.0f, 0.0f, 0.0f, 1.0f // top left
};
unsigned int indices[] = { // note that we start from 0!
0, 1, 3, // first triangle
1, 2, 3 // second triangle
};
void framebuffer_size_callback(GLFWwindow* window, int width, int height)
{
glViewport(0, 0, width, height);
}
int main() {
//printf("Current working dir: %s\n", get_current_dir_name());
glfwInit();
glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3); // 4.6 is highest
glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
GLFWwindow* window = glfwCreateWindow(800, 600, "Ogle", NULL, NULL);
if (window == NULL)
{
std::cout << "Failed to create GLFW window" << std::endl;
glfwTerminate();
return -1;
}
glfwMakeContextCurrent(window);
if (!gladLoadGLLoader((GLADloadproc)glfwGetProcAddress))
{
std::cout << "Failed to init GLAD" << std::endl;
return -1;
}
glViewport(0, 0, 800, 600);
glfwSetFramebufferSizeCallback(window, framebuffer_size_callback);
Shader shader = Shader("src/shaders/default.vert", "src/shaders/default.frag");
unsigned int VBO, VAO, EBO;
glGenBuffers(1, &VBO); // generate the buffer
glGenBuffers(1, &EBO);
glGenVertexArrays(1, &VAO); // generate array
glBindVertexArray(VAO); // bind array to apply "settings" to it
glBindBuffer(GL_ARRAY_BUFFER, VBO); // bind(activate) the buffer to the ARRAY_BUFFER
glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW); // upload the data
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, EBO);
glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(indices), indices, GL_STATIC_DRAW);
// position attribute
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)0); // configure how the vertex array looks
glEnableVertexAttribArray(0);
// color attribute
glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)(3 * sizeof(float))); // configure how the vertex array looks
glEnableVertexAttribArray(1);
//texture attribute
glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)(6 * sizeof(float))); // configure how the vertex array looks
glEnableVertexAttribArray(2);
//glPolygonMode(GL_FRONT_AND_BACK, GL_LINE); // wireframe mode
//{
// int nrAttributes;
// glGetIntegerv(GL_MAX_VERTEX_ATTRIBS, &nrAttributes);
// std::cout << "Maximum nr of vertex attributes supported: " << nrAttributes << std::endl;
//}
// Image/Texture stuffs
unsigned int texture1, texture2;
glGenTextures(1, &texture1);
glBindTexture(GL_TEXTURE_2D, texture1);
// set the texture wrapping/filtering options (on the currently bound texture object)
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_MIPMAP_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
// load and generate the texture
{
int width, height, nrChannels;
unsigned char *data = stbi_load("assets/container.jpg", &width, &height, &nrChannels, 0);
if (data)
{
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_RGB, GL_UNSIGNED_BYTE, data);
glGenerateMipmap(GL_TEXTURE_2D);
}
else
{
std::cout << "Failed to load texture" << std::endl;
}
stbi_image_free(data);
}
glGenTextures(2, &texture2);
glBindTexture(GL_TEXTURE_2D, texture2);
// set the texture wrapping/filtering options (on the currently bound texture object)
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_MIPMAP_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
// load and generate the texture
{
int width, height, nrChannels;
unsigned char *data = stbi_load("assets/awesomeface.png", &width, &height, &nrChannels, 0);
if (data)
{
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, data);
glGenerateMipmap(GL_TEXTURE_2D);
}
else
{
std::cout << "Failed to load texture" << std::endl;
}
stbi_image_free(data);
}
shader.use();
shader.setInt("texture1", 0);
shader.setInt("texture2", 1);
// game loop
while(!glfwWindowShouldClose(window))
{
processInput(window);
glClearColor(0.2f, 0.3f, 0.3f, 1.0f);
glClear(GL_COLOR_BUFFER_BIT);
//glUseProgram(shaderProgram); // this will activate the shader and use them for all subsequent shader and render calls
shader.use();
float timeValue = glfwGetTime();
float greenValue = (sin(timeValue) / 2.0f) + 0.5f;
shader.set4f("ourColor", 1.0f - greenValue, greenValue, (greenValue / 2.0f) + 0.25f, 1.0f);
shader.set1f("offset_x", greenValue - 0.5);
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_2D, texture1);
glActiveTexture(GL_TEXTURE1);
glBindTexture(GL_TEXTURE_2D, texture2);
glBindVertexArray(VAO); // activate the preconfigured settings
glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0); // :)
glBindVertexArray(0);
glfwSwapBuffers(window);
glfwPollEvents();
}
glfwTerminate();
return 0;
}
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