This is a lightweight implementation of the SDL3 library.
I really like the SDL3 library, but it saddens me that with each release of a new version, support for older systems is removed. Therefore, I decided to write a simpler version compatible at the API level. To support old and new systems, architectures, and operating systems. The project is being developed in C++98. This makes the code very portable.
To be described later (TBD)
# Install dependencies
$ sudo apt-get install libx11-dev
$ sudo apt-get install libgl1-mesa-dev
# Clone this repository & go into its directory
$ git clone https://github.com/JordanCpp/SDL3Lite.git
$ cd SDL3Lite
# Generate Makefile
$ cmake -Bout
$ cd out
# Build library
$ makeTBD
- Windows 95 and higher
- Linux (XLib) Debian 3 and higher
- OpenGL >= 1.0 and <= 4.6
- OpenGL 1.2
- Software
Boost Software License - Version 1.0 - August 17th, 2003
- Visual C++ 6.0 and higher
- GCC 3.0 and higher
- Borland C++ (Need a test)
- Clang (Need a test)
#include <SDL3/SDL.h>
#include <stdio.h>
int main()
{
SDL_Init(SDL_INIT_VIDEO);
SDL_Window* window = SDL_CreateWindow("Renderer", 640, 480, SDL_WINDOW_OPENGL);
if (window == NULL)
{
printf("Create window error: %s\n", SDL_GetError());
return 1;
}
SDL_Renderer* renderer = SDL_CreateRenderer(window, NULL);
if (renderer == NULL)
{
printf("Create renderer error: %s\n", SDL_GetError());
return 1;
}
bool done = false;
SDL_SetRenderDrawColor(renderer, 237, 28, 36, 0);
while (!done)
{
SDL_Event event;
while (SDL_PollEvent(&event))
{
if (event.type == SDL_EVENT_QUIT)
{
done = true;
}
}
SDL_RenderClear(renderer);
SDL_RenderPresent(renderer);
}
SDL_DestroyRenderer(renderer);
SDL_DestroyWindow(window);
SDL_Quit();
return 0;
}#define OPENGL_IMPLEMENTATION
#include "OpenGL.h"
#include <SDL3/SDL.h>
#include <math.h>
// Vertex Shader source code
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";
//Fragment Shader source code
const char* fragmentShaderSource = "#version 330 core\n"
"out vec4 FragColor;\n"
"void main()\n"
"{\n"
" FragColor = vec4(0.8f, 0.3f, 0.02f, 1.0f);\n"
"}\n\0";
#define WINDOW_WIDTH (640)
#define WINDOW_HEIGTH (480)
int main()
{
if (!SDL_Init(SDL_INIT_VIDEO))
{
SDL_Log("Init error: %s\n", SDL_GetError());
return 1;
}
SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 3);
SDL_Window* window = SDL_CreateWindow("OpenGL1", WINDOW_WIDTH, WINDOW_HEIGTH, SDL_WINDOW_OPENGL);
if (window == NULL)
{
SDL_Log("Create window error: %s\n", SDL_GetError());
return 1;
}
OpenGL_Compatibility_Init(3, 3);
SDL_GLContext* context = SDL_GL_CreateContext(window);
if (context == NULL)
{
SDL_Log("Create context error: %s\n", SDL_GetError());
return 1;
}
bool done = false;
// Specify the viewport of OpenGL in the Window
// In this case the viewport goes from x = 0, y = 0, to x = 800, y = 800
glViewport(0, 0, WINDOW_WIDTH, WINDOW_HEIGTH);
// Create Vertex Shader Object and get its reference
GLuint vertexShader = glCreateShader(GL_VERTEX_SHADER);
// Attach Vertex Shader source to the Vertex Shader Object
glShaderSource(vertexShader, 1, &vertexShaderSource, NULL);
// Compile the Vertex Shader into machine code
glCompileShader(vertexShader);
// Create Fragment Shader Object and get its reference
GLuint fragmentShader = glCreateShader(GL_FRAGMENT_SHADER);
// Attach Fragment Shader source to the Fragment Shader Object
glShaderSource(fragmentShader, 1, &fragmentShaderSource, NULL);
// Compile the Vertex Shader into machine code
glCompileShader(fragmentShader);
// Create Shader Program Object and get its reference
GLuint shaderProgram = glCreateProgram();
// Attach the Vertex and Fragment Shaders to the Shader Program
glAttachShader(shaderProgram, vertexShader);
glAttachShader(shaderProgram, fragmentShader);
// Wrap-up/Link all the shaders together into the Shader Program
glLinkProgram(shaderProgram);
// Delete the now useless Vertex and Fragment Shader objects
glDeleteShader(vertexShader);
glDeleteShader(fragmentShader);
// Vertices coordinates
GLfloat vertices[] =
{
-0.5f, -0.5f * float(sqrt(3)) / 3, 0.0f, // Lower left corner
0.5f, -0.5f * float(sqrt(3)) / 3, 0.0f, // Lower right corner
0.0f, 0.5f * float(sqrt(3)) * 2 / 3, 0.0f // Upper corner
};
// Create reference containers for the Vartex Array Object and the Vertex Buffer Object
GLuint VAO, VBO;
// Generate the VAO and VBO with only 1 object each
glGenVertexArrays(1, &VAO);
glGenBuffers(1, &VBO);
// Make the VAO the current Vertex Array Object by binding it
glBindVertexArray(VAO);
// Bind the VBO specifying it's a GL_ARRAY_BUFFER
glBindBuffer(GL_ARRAY_BUFFER, VBO);
// Introduce the vertices into the VBO
glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
// Configure the Vertex Attribute so that OpenGL knows how to read the VBO
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 3 * sizeof(float), (void*)0);
// Enable the Vertex Attribute so that OpenGL knows to use it
glEnableVertexAttribArray(0);
// Bind both the VBO and VAO to 0 so that we don't accidentally modify the VAO and VBO we created
glBindBuffer(GL_ARRAY_BUFFER, 0);
glBindVertexArray(0);
while (!done)
{
SDL_Event event;
while (SDL_PollEvent(&event))
{
if (event.type == SDL_EVENT_QUIT)
{
done = true;
}
}
// Specify the color of the background
glClearColor(0.07f, 0.13f, 0.17f, 1.0f);
// Clean the back buffer and assign the new color to it
glClear(GL_COLOR_BUFFER_BIT);
// Tell OpenGL which Shader Program we want to use
glUseProgram(shaderProgram);
// Bind the VAO so OpenGL knows to use it
glBindVertexArray(VAO);
// Draw the triangle using the GL_TRIANGLES primitive
glDrawArrays(GL_TRIANGLES, 0, 3);
SDL_GL_SwapWindow(window);
}
// Delete all the objects we've created
glDeleteVertexArrays(1, &VAO);
glDeleteBuffers(1, &VBO);
glDeleteProgram(shaderProgram);
SDL_GL_DestroyContext(context);
SDL_DestroyWindow(window);
SDL_Quit();
return 0;
}#define OPENGL_IMPLEMENTATION
#include "OpenGL.h"
#include <SDL3/SDL.h>
int main()
{
OpenGL_Compatibility_Init(1, 2);
if (!SDL_Init(SDL_INIT_VIDEO))
{
SDL_Log("Init error: %s\n", SDL_GetError());
return 1;
}
SDL_Window* window = SDL_CreateWindow("OpenGL1", 640, 480, SDL_WINDOW_OPENGL);
if (window == NULL)
{
SDL_Log("Create window error: %s\n", SDL_GetError());
return 1;
}
SDL_GLContext* context = SDL_GL_CreateContext(window);
if (context == NULL)
{
SDL_Log("Create context error: %s\n", SDL_GetError());
return 1;
}
bool done = false;
while (!done)
{
SDL_Event event;
while (SDL_PollEvent(&event))
{
if (event.type == SDL_EVENT_QUIT)
{
done = true;
}
}
glClear(GL_DEPTH_BUFFER_BIT);
glBegin(GL_POLYGON);
glColor3f(1.0f, 0.0f, 0.0f); glVertex3f(-0.6f, -0.75f, 0.5f);
glColor3f(0.0f, 1.0f, 0.0f); glVertex3f(0.6f , -0.75f, 0.0f);
glColor3f(0.0f, 0.0f, 1.0f); glVertex3f(0.0f , 0.75f , 0.0f);
glEnd();
SDL_GL_SwapWindow(window);
}
SDL_GL_DestroyContext(context);
SDL_DestroyWindow(window);
SDL_Quit();
return 0;
}
