commit 7686e292069e5d82de8ca59579b8190aae8934f8
parent 23ed0bb66855cfc578f9f9bd4c3c7572935e1df7
Author: amin <dev@aminmesbah.com>
Date: Fri, 17 Mar 2017 20:23:02 +0000
Fix lag and jitter.
I'm still working out the difference between getting input, updating
state, and rendering. Before I was rendering way more often than I
needed too. Now the rendering happens once per frame, as it should.
For each tick of the main loop, updates are processed as many times as
necessary to catch the game state up to where it should be based on
real-world time.
I'm now in a good position to simulate some basic physics for the
player's movement.
FossilOrigin-Name: 92b721937764d2ce5937e7f1fbcfa38d1b76211309f39278d0edffeaf0bb0c29
Diffstat:
| M | sdl_tunnel_runner.cpp | | | 239 | ++++++++++++++++++++++++++++++++++++++++--------------------------------------- |
1 file changed, 120 insertions(+), 119 deletions(-)
diff --git a/sdl_tunnel_runner.cpp b/sdl_tunnel_runner.cpp
@@ -1,4 +1,5 @@
#include <cmath>
+#include <inttypes.h>
#include <SDL.h>
#include <stdio.h>
#include <stdint.h>
@@ -37,7 +38,7 @@ typedef uint64_t uint64;
#define SECOND 1000.0f
#define FPS 60
#define MS_PER_FRAME (SECOND / FPS)
-#define UPDATES_PER_SECOND 65
+#define UPDATES_PER_SECOND 120
#define MS_PER_UPDATE (SECOND / UPDATES_PER_SECOND)
@@ -478,140 +479,140 @@ int main(void)
lag += elapsed_ms;
//printf("Lag: %d\n", lag);
- SDL_Event event;
-
- while (SDL_PollEvent(&event))
+ printf("%" PRIu64 ", %f\n", lag, MS_PER_UPDATE);
+ while (lag >= MS_PER_UPDATE)
{
- if (handle_event(&event))
+ SDL_Event event;
+
+ while (SDL_PollEvent(&event))
{
- running = false;
+ running = !handle_event(&event);
}
- }
- SDL_PumpEvents();
+ SDL_PumpEvents();
- dimension = sdl_get_window_dimension(window);
+ dimension = sdl_get_window_dimension(window);
- const uint8 *keystate = SDL_GetKeyboardState(0);
+ const uint8 *keystate = SDL_GetKeyboardState(0);
- if (keystate[SDL_SCANCODE_A])
- {
- rotation_offset -= MOVEMENT_SPEED;
- }
- if (keystate[SDL_SCANCODE_D])
- {
- rotation_offset += MOVEMENT_SPEED;
- }
- if (keystate[SDL_SCANCODE_W])
- {
- translation_offset += MOVEMENT_SPEED;
- }
- if (keystate[SDL_SCANCODE_S])
- {
- translation_offset -= MOVEMENT_SPEED;
- }
- if (keystate[SDL_SCANCODE_LEFT])
- {
- rotation_offset --;
- }
- if (keystate[SDL_SCANCODE_RIGHT])
- {
- rotation_offset ++;
- }
- if (keystate[SDL_SCANCODE_UP])
- {
- translation_offset ++;
- }
- if (keystate[SDL_SCANCODE_DOWN])
- {
- translation_offset --;
- }
-
-
- for (int controller_index = 0; controller_index < MAX_CONTROLLERS; ++controller_index)
- {
- if (SDL_GameControllerGetAttached(controller_handles[controller_index]))
+ if (keystate[SDL_SCANCODE_A])
{
- bool start = SDL_GameControllerGetButton(controller_handles[controller_index], SDL_CONTROLLER_BUTTON_START);
- bool back = SDL_GameControllerGetButton(controller_handles[controller_index], SDL_CONTROLLER_BUTTON_BACK);
- bool a_button = SDL_GameControllerGetButton(controller_handles[controller_index], SDL_CONTROLLER_BUTTON_A);
- bool b_button = SDL_GameControllerGetButton(controller_handles[controller_index], SDL_CONTROLLER_BUTTON_B);
- bool x_button = SDL_GameControllerGetButton(controller_handles[controller_index], SDL_CONTROLLER_BUTTON_X);
- bool y_button = SDL_GameControllerGetButton(controller_handles[controller_index], SDL_CONTROLLER_BUTTON_Y);
- bool left_shoulder = SDL_GameControllerGetButton(controller_handles[controller_index], SDL_CONTROLLER_BUTTON_LEFTSHOULDER);
- bool right_shoulder = SDL_GameControllerGetButton(controller_handles[controller_index], SDL_CONTROLLER_BUTTON_RIGHTSHOULDER);
-
- int16 stick_leftx = SDL_GameControllerGetAxis(controller_handles[controller_index], SDL_CONTROLLER_AXIS_LEFTX);
- int16 stick_lefty = SDL_GameControllerGetAxis(controller_handles[controller_index], SDL_CONTROLLER_AXIS_LEFTY);
- int16 stick_rightx = SDL_GameControllerGetAxis(controller_handles[controller_index], SDL_CONTROLLER_AXIS_RIGHTX);
- int16 stick_righty = SDL_GameControllerGetAxis(controller_handles[controller_index], SDL_CONTROLLER_AXIS_RIGHTY);
-
- if (start)
- {
- SDL_HapticRumblePlay(rumble_handles[controller_index], 0.5f, 2000);
- color_choice = '\0';
- }
- else
- {
- SDL_HapticRumbleStop(rumble_handles[controller_index]);
- }
+ rotation_offset -= MOVEMENT_SPEED;
+ }
+ if (keystate[SDL_SCANCODE_D])
+ {
+ rotation_offset += MOVEMENT_SPEED;
+ }
+ if (keystate[SDL_SCANCODE_W])
+ {
+ translation_offset += MOVEMENT_SPEED;
+ }
+ if (keystate[SDL_SCANCODE_S])
+ {
+ translation_offset -= MOVEMENT_SPEED;
+ }
+ if (keystate[SDL_SCANCODE_LEFT])
+ {
+ rotation_offset --;
+ }
+ if (keystate[SDL_SCANCODE_RIGHT])
+ {
+ rotation_offset ++;
+ }
+ if (keystate[SDL_SCANCODE_UP])
+ {
+ translation_offset ++;
+ }
+ if (keystate[SDL_SCANCODE_DOWN])
+ {
+ translation_offset --;
+ }
- if (back)
- {
- running = false;
- }
- // NOTE(amin): Buttons select colors.
- if (a_button)
- {
- color_choice = 'g';
- }
- if (b_button)
- {
- color_choice = 'r';
- }
- if (x_button)
- {
- color_choice = 'b';
- }
- if (y_button)
- {
- color_choice = 'y';
- }
- if (left_shoulder)
- {
- color_choice = 'm';
- }
- if (right_shoulder)
+ for (int controller_index = 0; controller_index < MAX_CONTROLLERS; ++controller_index)
+ {
+ if (SDL_GameControllerGetAttached(controller_handles[controller_index]))
{
- color_choice = 'c';
+ bool start = SDL_GameControllerGetButton(controller_handles[controller_index], SDL_CONTROLLER_BUTTON_START);
+ bool back = SDL_GameControllerGetButton(controller_handles[controller_index], SDL_CONTROLLER_BUTTON_BACK);
+ bool a_button = SDL_GameControllerGetButton(controller_handles[controller_index], SDL_CONTROLLER_BUTTON_A);
+ bool b_button = SDL_GameControllerGetButton(controller_handles[controller_index], SDL_CONTROLLER_BUTTON_B);
+ bool x_button = SDL_GameControllerGetButton(controller_handles[controller_index], SDL_CONTROLLER_BUTTON_X);
+ bool y_button = SDL_GameControllerGetButton(controller_handles[controller_index], SDL_CONTROLLER_BUTTON_Y);
+ bool left_shoulder = SDL_GameControllerGetButton(controller_handles[controller_index], SDL_CONTROLLER_BUTTON_LEFTSHOULDER);
+ bool right_shoulder = SDL_GameControllerGetButton(controller_handles[controller_index], SDL_CONTROLLER_BUTTON_RIGHTSHOULDER);
+
+ int16 stick_leftx = SDL_GameControllerGetAxis(controller_handles[controller_index], SDL_CONTROLLER_AXIS_LEFTX);
+ int16 stick_lefty = SDL_GameControllerGetAxis(controller_handles[controller_index], SDL_CONTROLLER_AXIS_LEFTY);
+ int16 stick_rightx = SDL_GameControllerGetAxis(controller_handles[controller_index], SDL_CONTROLLER_AXIS_RIGHTX);
+ int16 stick_righty = SDL_GameControllerGetAxis(controller_handles[controller_index], SDL_CONTROLLER_AXIS_RIGHTY);
+
+ if (start)
+ {
+ SDL_HapticRumblePlay(rumble_handles[controller_index], 0.5f, 2000);
+ color_choice = '\0';
+ }
+ else
+ {
+ SDL_HapticRumbleStop(rumble_handles[controller_index]);
+ }
+
+ if (back)
+ {
+ running = false;
+ }
+
+ // NOTE(amin): Buttons select colors.
+ if (a_button)
+ {
+ color_choice = 'g';
+ }
+ if (b_button)
+ {
+ color_choice = 'r';
+ }
+ if (x_button)
+ {
+ color_choice = 'b';
+ }
+ if (y_button)
+ {
+ color_choice = 'y';
+ }
+ if (left_shoulder)
+ {
+ color_choice = 'm';
+ }
+ if (right_shoulder)
+ {
+ color_choice = 'c';
+ }
+
+ rotation_offset += stick_leftx / 5000;
+ translation_offset -= stick_lefty / 5000;
+
+ int dampened_x_max = dimension.width / 2;
+ int dampened_x_min = -(dimension.width / 2);
+ int dampened_y_max = dimension.height / 2;
+ int dampened_y_min = -(dimension.height / 2);
+
+ int dampened_x = (stick_rightx - CONTROLLER_STICK_MIN) * (dampened_x_max - dampened_x_min) / (CONTROLLER_STICK_MAX - CONTROLLER_STICK_MIN) + dampened_x_min;
+ int dampened_y = (stick_righty - CONTROLLER_STICK_MIN) * (dampened_y_max - dampened_y_min) / (CONTROLLER_STICK_MAX - CONTROLLER_STICK_MIN) + dampened_y_min;
+
+ transform.look_shift_x = dimension.width / 2 + dampened_x;
+ transform.look_shift_y = dimension.height / 2 + dampened_y;
+ //printf("dimension.width / 2: %d\t damp_x: %d\t raw_x: %d\n", dimension.width / 2, dampened_x, stick_rightx);
+ //printf("dimension.height / 2: %d\t damp_y: %d\t raw_y: %d\n", dimension.height / 2, dampened_y, stick_righty);
}
-
- rotation_offset += stick_leftx / 5000;
- translation_offset -= stick_lefty / 5000;
-
- int dampened_x_max = dimension.width / 2;
- int dampened_x_min = -(dimension.width / 2);
- int dampened_y_max = dimension.height / 2;
- int dampened_y_min = -(dimension.height / 2);
-
- int dampened_x = (stick_rightx - CONTROLLER_STICK_MIN) * (dampened_x_max - dampened_x_min) / (CONTROLLER_STICK_MAX - CONTROLLER_STICK_MIN) + dampened_x_min;
- int dampened_y = (stick_righty - CONTROLLER_STICK_MIN) * (dampened_y_max - dampened_y_min) / (CONTROLLER_STICK_MAX - CONTROLLER_STICK_MIN) + dampened_y_min;
-
- transform.look_shift_x = dimension.width / 2 + dampened_x;
- transform.look_shift_y = dimension.height / 2 + dampened_y;
- //printf("dimension.width / 2: %d\t damp_x: %d\t raw_x: %d\n", dimension.width / 2, dampened_x, stick_rightx);
- //printf("dimension.height / 2: %d\t damp_y: %d\t raw_y: %d\n", dimension.height / 2, dampened_y, stick_righty);
}
- }
- printf("%d, %d\n", translation_offset, rotation_offset);
+ //printf("%d, %d\n", translation_offset, rotation_offset);
- while (lag >= MS_PER_UPDATE)
- {
- render_tunnel(global_back_buffer, texture, rotation_offset, translation_offset, color_choice);
- //render_texture(global_back_buffer, texture, rotation_offset, translation_offset, color_choice);
+ printf("\t%" PRIu64 ", %f\n", lag, MS_PER_UPDATE);
+ //render_tunnel(global_back_buffer, texture, rotation_offset, translation_offset, color_choice);
lag -= MS_PER_UPDATE;
}
+ render_tunnel(global_back_buffer, texture, rotation_offset, translation_offset, color_choice);
+ //render_texture(global_back_buffer, texture, rotation_offset, translation_offset, color_choice);
sdl_update_window(window, renderer, global_back_buffer);
if (elapsed_ms <= MS_PER_FRAME)
{
