Skip to content

Commit

Permalink
Added alien bullets.
Browse files Browse the repository at this point in the history
  • Loading branch information
@Grieverheart
Grieverheart committed May 26, 2018
1 parent 8af7bd8 commit d6f5211
Showing 1 changed file with 121 additions and 36 deletions.
157 changes: 121 additions & 36 deletions main.cpp
View file
Original file line number Diff line number Diff line change
@@ -1,5 1,6 @@
#include <cstdio>
#include <cstdint>
#include <limits>
#include <GL/glew.h>
#include <GLFW/glfw3.h>

Expand Down Expand Up @@ -83,6 84,22 @@ void key_callback(GLFWwindow* window, int key, int scancode, int action, int mod
}
}

/* Algorithm "xor" from p. 4 of Marsaglia, "Xorshift RNGs" */
uint32_t xorshift32(uint32_t* rng)
{
uint32_t x = *rng;
x ^= x << 13;
x ^= x >> 17;
x ^= x << 5;
*rng = x;
return x;
}

double random(uint32_t* rng)
{
return (double)xorshift32(rng) / std::numeric_limits<uint32_t>::max();
}

struct Buffer
{
size_t width, height;
Expand Down Expand Up @@ -583,16 600,30 @@ int main(int argc, char* argv[])
Sprite number_spritesheet = text_spritesheet;
number_spritesheet.data = 16 * 35;

Sprite bullet_sprite;
bullet_sprite.width = 1;
bullet_sprite.height = 3;
bullet_sprite.data = new uint8_t[3]
Sprite player_bullet_sprite;
player_bullet_sprite.width = 1;
player_bullet_sprite.height = 3;
player_bullet_sprite.data = new uint8_t[3]
{
1, // @
1, // @
1 // @
};

Sprite alien_bullet_sprite;
alien_bullet_sprite.width = 3;
alien_bullet_sprite.height = 7;
alien_bullet_sprite.data = new uint8_t[21]
{
0,1,0,
1,0,0,
0,1,0,
0,0,1,
0,1,0,
1,0,0,
0,1,0,
};


SpriteAnimation alien_animation[3];

Expand Down Expand Up @@ -641,6 672,10 @@ int main(int argc, char* argv[])
}

uint32_t clear_color = rgb_to_uint32(0, 128, 0);
uint32_t rng = 13;

size_t alien_update_frequency = 120;
size_t alien_update_timer = 0;

size_t score = 0;
size_t credits = 0;
Expand All @@ -655,12 690,23 @@ int main(int argc, char* argv[])
// Draw
buffer_draw_text(&buffer, text_spritesheet, "SCORE", 4, game.height - text_spritesheet.height - 7, rgb_to_uint32(128, 0, 0));

char credit_text[16];
sprintf(credit_text, "CREDIT lu", credits);
buffer_draw_text(&buffer, text_spritesheet, credit_text, 164, 7, rgb_to_uint32(128, 0, 0));
{
char credit_text[16];
sprintf(credit_text, "CREDIT lu", credits);
buffer_draw_text(&buffer, text_spritesheet, credit_text, 164, 7, rgb_to_uint32(128, 0, 0));
}

buffer_draw_number(&buffer, number_spritesheet, score, 4 2 * number_spritesheet.width, game.height - 2 * number_spritesheet.height - 12, rgb_to_uint32(128, 0, 0));


buffer_draw_number(&buffer, number_spritesheet, game.player.life, 4, 7, rgb_to_uint32(128, 0, 0));
size_t xp = 11 number_spritesheet.width;
for(size_t i = 0; i < game.player.life - 1; i)
{
buffer_draw_sprite(&buffer, player_sprite, xp, 7, rgb_to_uint32(128, 0, 0));
xp = player_sprite.width 2;
}

for(size_t i = 0; i < game.width; i)
{
buffer.data[game.width * 16 i] = rgb_to_uint32(128, 0, 0);
Expand Down Expand Up @@ -688,7 734,7 @@ int main(int argc, char* argv[])
for(size_t bi = 0; bi < game.num_bullets; bi)
{
const Bullet& bullet = game.bullets[bi];
const Sprite& sprite = bullet_sprite;
const Sprite& sprite = (bullet.dir > 0)? player_bullet_sprite: alien_bullet_sprite;
buffer_draw_sprite(&buffer, sprite, bullet.x, bullet.y, rgb_to_uint32(128, 0, 0));
}

Expand All @@ -714,54 760,91 @@ int main(int argc, char* argv[])

glfwSwapBuffers(window);

// Simulate aliens
for(size_t ai = 0; ai < game.num_aliens; ai)
{
const Alien& alien = game.aliens[ai];
if(alien.type == ALIEN_DEAD && death_counters[ai])
{
--death_counters[ai];
}
}

// Simulate bullets
for(size_t bi = 0; bi < game.num_bullets;)
for(size_t bi = 0; bi < game.num_bullets; bi)
{
game.bullets[bi].y = game.bullets[bi].dir;
if(game.bullets[bi].y >= game.height || game.bullets[bi].y < bullet_sprite.height)
if(game.bullets[bi].y >= game.height || game.bullets[bi].y < player_bullet_sprite.height)
{
game.bullets[bi] = game.bullets[game.num_bullets - 1];
--game.num_bullets;
continue;
}

// Check hit
for(size_t ai = 0; ai < game.num_aliens; ai)
// Alien bullet
if(game.bullets[bi].dir < 0)
{
const Alien& alien = game.aliens[ai];
if(alien.type == ALIEN_DEAD) continue;

const SpriteAnimation& animation = alien_animation[alien.type - 1];
size_t current_frame = animation.time / animation.frame_duration;
const Sprite& alien_sprite = *animation.frames[current_frame];
bool overlap = sprite_overlap_check(
bullet_sprite, game.bullets[bi].x, game.bullets[bi].y,
alien_sprite, alien.x, alien.y
alien_bullet_sprite, game.bullets[bi].x, game.bullets[bi].y,
player_sprite, game.player.x, game.player.y
);
if(overlap)
{
score = 10 * (4 - game.aliens[ai].type);
game.aliens[ai].type = ALIEN_DEAD;
// NOTE: Hack to recenter death sprite
game.aliens[ai].x -= (alien_death_sprite.width - alien_sprite.width)/2;
--game.player.life;
if(game.player.life == 0)
{
game_running = false;
break;
}
game.bullets[bi] = game.bullets[game.num_bullets - 1];
--game.num_bullets;
continue;
}
}
// Player bullet
else
{
// Check hit
for(size_t ai = 0; ai < game.num_aliens; ai)
{
const Alien& alien = game.aliens[ai];
if(alien.type == ALIEN_DEAD) continue;

const SpriteAnimation& animation = alien_animation[alien.type - 1];
size_t current_frame = animation.time / animation.frame_duration;
const Sprite& alien_sprite = *animation.frames[current_frame];
bool overlap = sprite_overlap_check(
player_bullet_sprite, game.bullets[bi].x, game.bullets[bi].y,
alien_sprite, alien.x, alien.y
);
if(overlap)
{
score = 10 * (4 - game.aliens[ai].type);
game.aliens[ai].type = ALIEN_DEAD;
// NOTE: Hack to recenter death sprite
game.aliens[ai].x -= (alien_death_sprite.width - alien_sprite.width)/2;
game.bullets[bi] = game.bullets[game.num_bullets - 1];
--game.num_bullets;
continue;
}
}
}
}

bi;
// Simulate aliens
for(size_t ai = 0; ai < game.num_aliens; ai)
{
const Alien& alien = game.aliens[ai];
if(alien.type == ALIEN_DEAD && death_counters[ai])
{
--death_counters[ai];
}
}

if(alien_update_timer == alien_update_frequency - 1)
{
alien_update_timer = 0;
size_t rai = game.num_aliens * random(&rng);
while(game.aliens[rai].type == ALIEN_DEAD)
{
rai = game.num_aliens * random(&rng);
}
const Sprite& alien_sprite = *alien_animation[game.aliens[rai].type - 1].frames[0];
game.bullets[game.num_bullets].x = game.aliens[rai].x alien_sprite.width / 2;
game.bullets[game.num_bullets].y = game.aliens[rai].y - alien_bullet_sprite.height;
game.bullets[game.num_bullets].dir = -2;
game.num_bullets;
}
alien_update_timer;

// Simulate player
player_move_dir = 2 * move_dir;
Expand Down Expand Up @@ -804,6 887,8 @@ int main(int argc, char* argv[])

delete[] text_spritesheet.data;
delete[] alien_death_sprite.data;
delete[] player_bullet_sprite.data;
delete[] alien_bullet_sprite.data;

for(size_t i = 0; i < 3; i)
{
Expand Down

0 comments on commit d6f5211

Please sign in to comment.