Files
raylib/examples/shapes/shapes_simple_particles.c
2025-10-15 19:59:28 +02:00

277 lines
11 KiB
C

/*******************************************************************************************
*
* raylib [shapes] example - simple 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 3000 // Max number particles
//----------------------------------------------------------------------------------
// Types and Structures Definition
//----------------------------------------------------------------------------------
typedef enum ParticleType {
WATER = 0,
SMOKE,
FIRE
} ParticleType;
static const char particleTypeNames[3][10] = { "WATER", "SMOKE", "FIRE" };
typedef struct Particle {
ParticleType type; // Particle type (WATER, SMOKE, FIRE)
Vector2 position; // Particle position on screen
Vector2 velocity; // Particle current speed and direction
float radius; // Particle radius
Color color; // Particle color
float lifeTime; // Particle life time
bool alive; // Particle alive: inside screen and life time
} 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 void EmitParticle(CircularBuffer *circularBuffer, Vector2 emitterPosition, ParticleType type);
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 - simple 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; // Negative: on average every -X frames. Positive: particles per frame
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 (emissionRate < 0)
{
if (rand()%(-emissionRate) == 0) EmitParticle(&circularBuffer, emitterPosition, currentType);
}
else
{
for (int i = 0; i <= emissionRate; ++i) EmitParticle(&circularBuffer, emitterPosition, currentType);
}
// 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++;
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--;
if (IsMouseButtonDown(MOUSE_LEFT_BUTTON)) emitterPosition = GetMousePosition();
//----------------------------------------------------------------------------------
// 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);
if (emissionRate < 0) DrawText(TextFormat("Particles every %d frames | Type: %s", -emissionRate, particleTypeNames[currentType]), 15, 95, 10, DARKGRAY);
else DrawText(TextFormat("%d Particles per frame | Type: %s", emissionRate + 1, particleTypeNames[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 void EmitParticle(CircularBuffer *circularBuffer, Vector2 emitterPosition, ParticleType type)
{
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 = type;
float speed = (float)(rand()%10)/5.0f;
switch (type)
{
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: break;
}
float direction = (float)(rand()%360);
newParticle->velocity = (Vector2){ speed*cosf(direction*DEG2RAD), speed*sinf(direction*DEG2RAD) };
}
}
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*215.0f);
circularBuffer->buffer[i].velocity.y -= 0.05f; // Upwards
circularBuffer->buffer[i].position.y += circularBuffer->buffer[i].velocity.y;
circularBuffer->buffer[i].radius -= 0.15f; // Decrement radius: fire shrinks
circularBuffer->buffer[i].color.g -= 3; // 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
Vector2 center = circularBuffer->buffer[i].position;
float radius = circularBuffer->buffer[i].radius;
if ((center.x < -radius) || (center.x > screenWidth + radius) ||
(center.y < -radius) || (center.y > screenHeight + radius))
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);
}
}
}