setup git repo

1 files changed, 125 insertions, 0 deletions

diff --git a/main.c b/main.c
new file mode 100644
index 0000000..e5e0f51
--- /dev/null
+++ b/main.c
@@ -0,0 +1,125 @@
+#include <math.h>
+#include <SDL2/SDL.h>
+#include <glad/glad.h>
+
+int main(int argc, char *argv[])
+{
+	int width = 1920;
+	int height = 1080;
+	
+	if (SDL_Init(SDL_INIT_VIDEO) != 0)
+	{
+		printf("Error initialising SDL2: %s\n", SDL_GetError());
+		return 0;
+	};
+
+	// initialise window with opengl flag
+	SDL_Window *window = SDL_CreateWindow("SDL Test", 
+		SDL_WINDOWPOS_UNDEFINED, 
+		SDL_WINDOWPOS_UNDEFINED, 
+		width, 
+		height, 
+		SDL_WINDOW_OPENGL);
+	
+	// create an opengl context
+	SDL_GLContext context = SDL_GL_CreateContext(window);
+	if (!context)
+	{
+		printf("OpenGL context creation failed: %s\n", SDL_GetError());
+		return -1;
+	}
+
+	// load glad
+	if (!gladLoadGLLoader((GLADloadproc)SDL_GL_GetProcAddress)) {
+	    printf("Failed to initialize Glad\n");
+	    return 1;
+	}
+
+	// opengl rendering and shader stuff here
+	// @todo: 
+	// have to learn how to setup shaders and other things with modern opengl (4.5+)
+  const char* vertexSource =
+      "#version 330 core\n"
+      "layout(location = 0) in vec3 position;"
+      "void main() {"
+      "    gl_Position = vec4(position, 1.0);"
+      "}";
+
+  const char* fragmentSource =
+      "#version 330 core\n"
+      "out vec4 fragColor;"
+      "void main() {"
+      "    fragColor = vec4(1.0, 0.0, 0.0, 1.0);"
+      "}";
+
+  GLuint vertexShader = glCreateShader(GL_VERTEX_SHADER);
+  glShaderSource(vertexShader, 1, &vertexSource, NULL);
+  glCompileShader(vertexShader);
+
+  GLuint fragmentShader = glCreateShader(GL_FRAGMENT_SHADER);
+  glShaderSource(fragmentShader, 1, &fragmentSource, NULL);
+  glCompileShader(fragmentShader);
+
+  GLuint shaderProgram = glCreateProgram();
+  glAttachShader(shaderProgram, vertexShader);
+  glAttachShader(shaderProgram, fragmentShader);
+  glLinkProgram(shaderProgram);
+  glUseProgram(shaderProgram);
+
+  glDeleteShader(vertexShader);
+  glDeleteShader(fragmentShader);
+
+  GLfloat vertices[] = {
+      -0.5f, -0.5f, 0.0f,
+       0.5f, -0.5f, 0.0f,
+       0.0f,  0.5f, 0.0f
+  };
+
+  GLuint VBO, VAO;
+  glGenVertexArrays(1, &VAO);
+  glGenBuffers(1, &VBO);
+
+  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(GLfloat), (GLvoid*)0);
+  glEnableVertexAttribArray(0);
+
+  glBindBuffer(GL_ARRAY_BUFFER, 0);
+  glBindVertexArray(0);
+	for(;;)
+	{
+		SDL_Event ev;
+		while(SDL_PollEvent(&ev))
+		{
+			if (ev.type == SDL_QUIT)
+			{
+				return 0;
+			}
+		}
+
+		// opengl rendering code here
+		// @note: this part is more or less the same
+		// as with my learn opengl experiments
+    glClearColor(0.2f, 0.3f, 0.3f, 1.0f);
+    glClear(GL_COLOR_BUFFER_BIT);
+
+    glUseProgram(shaderProgram);
+    glBindVertexArray(VAO);
+    glDrawArrays(GL_TRIANGLES, 0, 3);
+    glBindVertexArray(0);
+
+    SDL_GL_SwapWindow(window);
+	}
+  // opengl free calls
+  glDeleteVertexArrays(1, &VAO);
+  glDeleteBuffers(1, &VBO);
+  glDeleteProgram(shaderProgram);
+  // sdl free calls
+	SDL_GL_DeleteContext(context);
+	SDL_DestroyWindow(window);
+	SDL_Quit();
+	return 0;
+}