raylib/examples/shapes/shapes_particles.c
2025-10-12 07:52:54 +02:00

264 lines
11 KiB
C

/*******************************************************************************************
*
* raylib [shapes] example - particles
*
* Example complexity rating: [★☆☆☆] 1/4
*
* Example originally created with raylib 5.6, last time updated with raylib 5.6
*
* Example contributed by Jordi Santonja (@JordSant)
*
* Example licensed under an unmodified zlib/libpng license, which is an OSI-certified,
* BSD-like license that allows static linking with closed source software
*
* Copyright (c) 2025 Jordi Santonja (@JordSant)
*
********************************************************************************************/
#include "raylib.h"
#include <stdlib.h> // Required for: calloc(), free()
#include <math.h> // Required for: cosf(), sinf()
#define MAX_PARTICLES 300 // Max number particles
//----------------------------------------------------------------------------------
// Types and Structures Definition
//----------------------------------------------------------------------------------
typedef enum ParticleType {
WATER = 0,
SMOKE,
FIRE
} ParticleType;
static const char particleTypesChar[3][10] = { "WATER", "SMOKE", "FIRE" };
typedef struct Particle {
Vector2 position; // Particle position on screen
Vector2 velocity; // Particle current speed and direction
bool alive; // Particle alive: inside screen and life time
float lifeTime; // Particle life time
ParticleType type; // Particle type (WATER, SMOKE, FIRE)
float radius; // Particle radius
Color color; // Particle color
} Particle;
typedef struct CircularBuffer {
int head; // Index for the next write
int tail; // Index for the next read
Particle* buffer; // Particle buffer array
} CircularBuffer;
//----------------------------------------------------------------------------------
// Module Functions Declaration
//----------------------------------------------------------------------------------
static Particle* AddToCircularBuffer(CircularBuffer* circularBuffer);
static void UpdateParticles(CircularBuffer* circularBuffer, int screenWidth, int screenHeight);
static void UpdateCircularBuffer(CircularBuffer* circularBuffer);
static void DrawParticles(CircularBuffer* circularBuffer);
//------------------------------------------------------------------------------------
// Program main entry point
//------------------------------------------------------------------------------------
int main(void)
{
// Initialization
//--------------------------------------------------------------------------------------
const int screenWidth = 800;
const int screenHeight = 450;
InitWindow(screenWidth, screenHeight, "raylib [shapes] example - particles");
// Definition of particles
Particle* particles = (Particle*)RL_CALLOC(MAX_PARTICLES, sizeof(Particle)); // Particle array
CircularBuffer circularBuffer = { 0, 0, particles };
// Particle emitter parameters
int emissionRate = 2;
ParticleType currentType = WATER;
Vector2 emitterPosition = { screenWidth / 2.0f, screenHeight / 2.0f };
SetTargetFPS(60); // Set our game to run at 60 frames-per-second
//--------------------------------------------------------------------------------------
// Main game loop
while (!WindowShouldClose()) // Detect window close button or ESC key
{
// Update
//----------------------------------------------------------------------------------
// Emit new particles: when emissionRate is 1, emit every frame
if ((rand() % emissionRate) == 0)
{
Particle* newParticle = AddToCircularBuffer(&circularBuffer);
// If buffer is full, newParticle is NULL
if (newParticle != NULL)
{
// Fill particle properties
newParticle->position = emitterPosition;
newParticle->alive = true;
newParticle->lifeTime = 0.0f;
newParticle->type = currentType;
float speed = (float)(rand() % 10) / 5.0f;
switch (currentType)
{
case WATER:
newParticle->radius = 5.0f;
newParticle->color = BLUE;
break;
case SMOKE:
newParticle->radius = 7.0f;
newParticle->color = GRAY;
break;
case FIRE:
newParticle->radius = 10.0f;
newParticle->color = YELLOW;
speed /= 10.0f;
break;
default:
newParticle->radius = 5.0f;
newParticle->color = WHITE;
break;
}
float direction = (float)(rand() % 360);
newParticle->velocity = (Vector2){ speed * cosf(direction * DEG2RAD), speed * sinf(direction * DEG2RAD) };
}
}
// Update the parameters of each particle
UpdateParticles(&circularBuffer, screenWidth, screenHeight);
// Remove dead particles from the circular buffer
UpdateCircularBuffer(&circularBuffer);
// Change Particle Emission Rate (UP/DOWN arrows)
if (IsKeyPressed(KEY_UP) && (emissionRate > 1))
--emissionRate;
if (IsKeyPressed(KEY_DOWN))
++emissionRate;
// Change Particle Type (LEFT/RIGHT arrows)
if (IsKeyPressed(KEY_RIGHT))
(currentType == FIRE) ? currentType = WATER : ++currentType;
if (IsKeyPressed(KEY_LEFT))
(currentType == WATER) ? currentType = FIRE : --currentType;
//----------------------------------------------------------------------------------
// Draw
//----------------------------------------------------------------------------------
BeginDrawing();
ClearBackground(RAYWHITE);
// Call the function with a loop to draw all particles
DrawParticles(&circularBuffer);
// Draw UI and Instructions
DrawRectangle(5, 5, 315, 75, Fade(SKYBLUE, 0.5f));
DrawRectangleLines(5, 5, 315, 75, BLUE);
DrawText("CONTROLS:", 15, 15, 10, BLACK);
DrawText("UP/DOWN: Change Particle Emission Rate", 15, 35, 10, BLACK);
DrawText("LEFT/RIGHT: Change Particle Type (Water, Smoke, Fire)", 15, 55, 10, BLACK);
DrawText(TextFormat("Emission Rate: %d | Type: %s", emissionRate, particleTypesChar[currentType]), 15, 95, 10, DARKGRAY);
DrawFPS(screenWidth - 80, 10);
EndDrawing();
//----------------------------------------------------------------------------------
}
// De-Initialization
//--------------------------------------------------------------------------------------
RL_FREE(particles); // Free particles array data
CloseWindow(); // Close window and OpenGL context
//--------------------------------------------------------------------------------------
return 0;
}
//----------------------------------------------------------------------------------
// Module Functions Definition
//----------------------------------------------------------------------------------
static Particle* AddToCircularBuffer(CircularBuffer* circularBuffer)
{
Particle* particle = NULL;
// Check if buffer full
if (((circularBuffer->head + 1) % MAX_PARTICLES) != circularBuffer->tail)
{
// Add new particle to the head position and advance head
particle = &circularBuffer->buffer[circularBuffer->head];
circularBuffer->head = (circularBuffer->head + 1) % MAX_PARTICLES;
}
return particle;
}
static void UpdateParticles(CircularBuffer* circularBuffer, int screenWidth, int screenHeight)
{
for (int i = circularBuffer->tail; i != circularBuffer->head; i = (i + 1) % MAX_PARTICLES)
{
// Update particle life and positions
circularBuffer->buffer[i].lifeTime += 1.0f / 60.0f; // 60 FPS -> 1/60 seconds per frame
switch (circularBuffer->buffer[i].type)
{
case WATER:
circularBuffer->buffer[i].position.x += circularBuffer->buffer[i].velocity.x;
circularBuffer->buffer[i].velocity.y += 0.2f; // Gravity
circularBuffer->buffer[i].position.y += circularBuffer->buffer[i].velocity.y;
break;
case SMOKE:
circularBuffer->buffer[i].position.x += circularBuffer->buffer[i].velocity.x;
circularBuffer->buffer[i].velocity.y -= 0.05f; // Upwards
circularBuffer->buffer[i].position.y += circularBuffer->buffer[i].velocity.y;
circularBuffer->buffer[i].radius += 0.5f; // Increment radius: smoke expands
circularBuffer->buffer[i].color.a -= 4; // Decrement alpha: smoke fades
if (circularBuffer->buffer[i].color.a < 4) // If alpha transparent, particle dies
circularBuffer->buffer[i].alive = false;
break;
case FIRE:
// Add a little horizontal oscillation to fire particles
circularBuffer->buffer[i].position.x += circularBuffer->buffer[i].velocity.x + cosf(circularBuffer->buffer[i].lifeTime * 10.0f);
circularBuffer->buffer[i].velocity.y -= 0.005f; // Upwards
circularBuffer->buffer[i].position.y += circularBuffer->buffer[i].velocity.y;
circularBuffer->buffer[i].radius -= 0.05f; // Decrement radius: fire shrinks
circularBuffer->buffer[i].color.g -= 1; // Decrement green: fire turns reddish starting from yellow
if (circularBuffer->buffer[i].radius <= 0.02f) // If radius too small, particle dies
circularBuffer->buffer[i].alive = false;
break;
default: break;
}
// Disable particle when out of screen
if ((circularBuffer->buffer[i].position.x < 0) ||
(circularBuffer->buffer[i].position.x > screenWidth) ||
(circularBuffer->buffer[i].position.y < 0) ||
(circularBuffer->buffer[i].position.y > screenHeight))
circularBuffer->buffer[i].alive = false;
}
}
static void UpdateCircularBuffer(CircularBuffer* circularBuffer)
{
// Update circular buffer: advance tail over dead particles
while ((circularBuffer->tail != circularBuffer->head) &&
!circularBuffer->buffer[circularBuffer->tail].alive)
{
circularBuffer->tail = (circularBuffer->tail + 1) % MAX_PARTICLES;
}
}
static void DrawParticles(CircularBuffer* circularBuffer)
{
for (int i = circularBuffer->tail; i != circularBuffer->head; i = (i + 1) % MAX_PARTICLES)
{
if (circularBuffer->buffer[i].alive)
{
DrawCircleV(circularBuffer->buffer[i].position,
circularBuffer->buffer[i].radius,
circularBuffer->buffer[i].color);
}
}
}