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#include "GL/glew.h"
#include "SDL2/SDL.h"
#include "prge.h"
#include "game.h"
#include "game.c"
void process_mouse_pos(Input *input, S32 x, S32 y)
{
V2 pos = v2((F32)x, (F32)y);
if (input->first_mouse) {
input->mouse_pos = pos;
input->first_mouse = 0;
}
input->last_mouse_pos = input->mouse_pos;
input->mouse_pos = pos;
input->mouse_offset = v2sub(input->mouse_pos,
input->last_mouse_pos);
}
void process_window_resize()
{
}
void process_key(U8 state, Key *key)
{
key->state = (state == SDL_PRESSED) ? KeyState_PRESS : KeyState_RELEASE;
}
void process_keyboard(Input *input, SDL_KeyboardEvent *key)
{
switch (key->keysym.scancode) {
case SDL_SCANCODE_D:
process_key(key->state, &input->move_right);
break;
case SDL_SCANCODE_W:
process_key(key->state, &input->move_forward);
break;
case SDL_SCANCODE_A:
process_key(key->state, &input->move_left);
break;
case SDL_SCANCODE_S:
process_key(key->state, &input->move_backward);
break;
case SDL_SCANCODE_E:
process_key(key->state, &input->move_up);
break;
case SDL_SCANCODE_Q:
process_key(key->state, &input->move_down);
break;
case SDL_SCANCODE_SPACE:
process_key(key->state, &input->jump);
break;
case SDL_SCANCODE_RIGHT:
process_key(key->state, &input->action_right);
break;
case SDL_SCANCODE_UP:
process_key(key->state, &input->action_up);
break;
case SDL_SCANCODE_LEFT:
process_key(key->state, &input->action_left);
break;
case SDL_SCANCODE_DOWN:
process_key(key->state, &input->action_down);
break;
case SDL_SCANCODE_ESCAPE:
process_key(key->state, &input->exit);
break;
default:
break;
}
}
void handle_events(Input *input)
{
SDL_Event event;
while (SDL_PollEvent(&event)) {
switch (event.type) {
case SDL_KEYDOWN:
case SDL_KEYUP:
process_keyboard(input, &event.key);
break;
case SDL_MOUSEMOTION:
process_mouse_pos(input, event.motion.x, event.motion.y);
break;
case SDL_WINDOWEVENT_RESIZED:
process_window_resize();
break;
default:
break;
}
}
}
F32 get_elapsed_seconds(U64 cur, U64 last)
{
F32 result = ((F32)cur-(F32)last)/1000.0f;
return result;
}
F32 lock_framerate(U64 last, F32 target)
{
F32 target_mspf = 1000.0f/target;
F32 elapsed = get_elapsed_seconds(SDL_GetTicks64(), last)*1000.0f;
if (elapsed < target_mspf) {
/* F32 sleep = target_mspf-elapsed-1.0f; */
F32 sleep = target_mspf-elapsed;
if (sleep > 0.0f)
SDL_Delay(sleep);
/*
do {
elapsed = get_elapsed_seconds(SDL_GetTicks64(), last)*1000.0f;
} while (elapsed < target_mspf);
*/
}
F32 dt = get_elapsed_seconds(SDL_GetTicks64(), last);
return dt;
}
B32 sdl_init(S32 width, S32 height,
SDL_Window **window,
SDL_GLContext **context)
{
if (SDL_Init(SDL_INIT_VIDEO)) {
SDL_Log("[ERROR] : SDL : %s\n", SDL_GetError());
return 0;
}
SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 3);
SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK,
SDL_GL_CONTEXT_PROFILE_CORE);
U32 flags = SDL_WINDOW_OPENGL | SDL_WINDOW_RESIZABLE;
(*window) = SDL_CreateWindow("prge game example",
SDL_WINDOWPOS_CENTERED,
SDL_WINDOWPOS_CENTERED,
width, height, flags);
if (!(*window)) {
SDL_Log("[ERROR] : SDL : %s\n", SDL_GetError());
return 0;
}
(*context) = SDL_GL_CreateContext((*window));
if (!(*context)) {
SDL_Log("[ERROR] : SDL : %s\n", SDL_GetError());
return 0;
}
GLenum error = glewInit();
if (error != GLEW_OK) {
SDL_Log("[ERROR] : GLEW : %s\n", glewGetErrorString(error));
return 0;
}
return 1;
}
int main(void)
{
/* NOTE(pryazha): Engine init */
Input input = input_init();
S32 width = 800, height = 600;
/* NOTE(pryazha): SDL init */
SDL_Window *window;
SDL_GLContext *context;
if (!sdl_init(width, height, &window, &context)) {
SDL_Quit();
return 1;
}
/* NOTE(pryazha): Game init */
State state = {0};
game_init(&state);
U64 last = SDL_GetTicks64();
while (input.is_running) {
handle_events(&input);
input.dt = lock_framerate(last, 60.0f);
last = SDL_GetTicks64();
game_update_and_render(&state, &input);
input_update(&input);
SDL_GL_SwapWindow(window);
}
game_clear(&state);
SDL_GL_DeleteContext(context);
SDL_DestroyWindow(window);
SDL_Quit();
return 0;
}
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