godot/drivers/gles3/shaders/particles.glsl

513 lines
13 KiB
GLSL

/* clang-format off */
#[modes]
mode_default =
#[specializations]
MODE_3D = false
USERDATA1_USED = false
USERDATA2_USED = false
USERDATA3_USED = false
USERDATA4_USED = false
USERDATA5_USED = false
USERDATA6_USED = false
#[vertex]
#define SDF_MAX_LENGTH 16384.0
layout(std140) uniform GlobalShaderUniformData { //ubo:1
vec4 global_shader_uniforms[MAX_GLOBAL_SHADER_UNIFORMS];
};
// This needs to be outside clang-format so the ubo comment is in the right place
#ifdef MATERIAL_UNIFORMS_USED
layout(std140) uniform MaterialUniforms{ //ubo:2
#MATERIAL_UNIFORMS
};
#endif
/* clang-format on */
#define MAX_ATTRACTORS 32
#define ATTRACTOR_TYPE_SPHERE uint(0)
#define ATTRACTOR_TYPE_BOX uint(1)
#define ATTRACTOR_TYPE_VECTOR_FIELD uint(2)
struct Attractor {
mat4 transform;
vec4 extents; // Extents or radius. w-channel is padding.
uint type;
float strength;
float attenuation;
float directionality;
};
#define MAX_COLLIDERS 32
#define COLLIDER_TYPE_SPHERE uint(0)
#define COLLIDER_TYPE_BOX uint(1)
#define COLLIDER_TYPE_SDF uint(2)
#define COLLIDER_TYPE_HEIGHT_FIELD uint(3)
#define COLLIDER_TYPE_2D_SDF uint(4)
struct Collider {
mat4 transform;
vec4 extents; // Extents or radius. w-channel is padding.
uint type;
float scale;
float pad0;
float pad1;
};
layout(std140) uniform FrameData { //ubo:0
bool emitting;
uint cycle;
float system_phase;
float prev_system_phase;
float explosiveness;
float randomness;
float time;
float delta;
float particle_size;
float amount_ratio;
float pad1;
float pad2;
uint random_seed;
uint attractor_count;
uint collider_count;
uint frame;
mat4 emission_transform;
vec3 emitter_velocity;
float interp_to_end;
Attractor attractors[MAX_ATTRACTORS];
Collider colliders[MAX_COLLIDERS];
};
#define PARTICLE_FLAG_ACTIVE uint(1)
#define PARTICLE_FLAG_STARTED uint(2)
#define PARTICLE_FLAG_TRAILED uint(4)
#define PARTICLE_FRAME_MASK uint(0xFFFF)
#define PARTICLE_FRAME_SHIFT uint(16)
// ParticleData
layout(location = 0) in highp vec4 color;
layout(location = 1) in highp vec4 velocity_flags;
layout(location = 2) in highp vec4 custom;
layout(location = 3) in highp vec4 xform_1;
layout(location = 4) in highp vec4 xform_2;
#ifdef MODE_3D
layout(location = 5) in highp vec4 xform_3;
#endif
#ifdef USERDATA1_USED
in highp vec4 userdata1;
#endif
#ifdef USERDATA2_USED
in highp vec4 userdata2;
#endif
#ifdef USERDATA3_USED
in highp vec4 userdata3;
#endif
#ifdef USERDATA4_USED
in highp vec4 userdata4;
#endif
#ifdef USERDATA5_USED
in highp vec4 userdata5;
#endif
#ifdef USERDATA6_USED
in highp vec4 userdata6;
#endif
out highp vec4 out_color; //tfb:
out highp vec4 out_velocity_flags; //tfb:
out highp vec4 out_custom; //tfb:
out highp vec4 out_xform_1; //tfb:
out highp vec4 out_xform_2; //tfb:
#ifdef MODE_3D
out highp vec4 out_xform_3; //tfb:MODE_3D
#endif
#ifdef USERDATA1_USED
out highp vec4 out_userdata1; //tfb:USERDATA1_USED
#endif
#ifdef USERDATA2_USED
out highp vec4 out_userdata2; //tfb:USERDATA2_USED
#endif
#ifdef USERDATA3_USED
out highp vec4 out_userdata3; //tfb:USERDATA3_USED
#endif
#ifdef USERDATA4_USED
out highp vec4 out_userdata4; //tfb:USERDATA4_USED
#endif
#ifdef USERDATA5_USED
out highp vec4 out_userdata5; //tfb:USERDATA5_USED
#endif
#ifdef USERDATA6_USED
out highp vec4 out_userdata6; //tfb:USERDATA6_USED
#endif
uniform sampler2D height_field_texture; //texunit:0
uniform float lifetime;
uniform bool clear;
uniform uint total_particles;
uniform bool use_fractional_delta;
uint hash(uint x) {
x = ((x >> uint(16)) ^ x) * uint(0x45d9f3b);
x = ((x >> uint(16)) ^ x) * uint(0x45d9f3b);
x = (x >> uint(16)) ^ x;
return x;
}
vec3 safe_normalize(vec3 direction) {
const float EPSILON = 0.001;
if (length(direction) < EPSILON) {
return vec3(0.0);
}
return normalize(direction);
}
// Needed whenever 2D sdf texture is read from as it is packed in RGBA8.
float vec4_to_float(vec4 p_vec) {
return dot(p_vec, vec4(1.0 / (255.0 * 255.0 * 255.0), 1.0 / (255.0 * 255.0), 1.0 / 255.0, 1.0)) * 2.0 - 1.0;
}
#GLOBALS
void main() {
bool apply_forces = true;
bool apply_velocity = true;
float local_delta = delta;
float mass = 1.0;
bool restart = false;
bool restart_position = false;
bool restart_rotation_scale = false;
bool restart_velocity = false;
bool restart_color = false;
bool restart_custom = false;
mat4 xform = mat4(1.0);
uint flags = 0u;
if (clear) {
out_color = vec4(1.0);
out_custom = vec4(0.0);
out_velocity_flags = vec4(0.0);
} else {
out_color = color;
out_velocity_flags = velocity_flags;
out_custom = custom;
xform[0] = xform_1;
xform[1] = xform_2;
#ifdef MODE_3D
xform[2] = xform_3;
#endif
xform = transpose(xform);
flags = floatBitsToUint(velocity_flags.w);
#ifdef USERDATA1_USED
out_userdata1 = userdata1;
#endif
#ifdef USERDATA2_USED
out_userdata2 = userdata2;
#endif
#ifdef USERDATA3_USED
out_userdata3 = userdata3;
#endif
#ifdef USERDATA4_USED
out_userdata4 = userdata4;
#endif
#ifdef USERDATA5_USED
out_userdata5 = userdata5;
#endif
#ifdef USERDATA6_USED
out_userdata6 = userdata6;
#endif
}
//clear started flag if set
flags &= ~PARTICLE_FLAG_STARTED;
bool collided = false;
vec3 collision_normal = vec3(0.0);
float collision_depth = 0.0;
vec3 attractor_force = vec3(0.0);
#if !defined(DISABLE_VELOCITY)
if (bool(flags & PARTICLE_FLAG_ACTIVE)) {
xform[3].xyz += out_velocity_flags.xyz * local_delta;
}
#endif
uint index = uint(gl_VertexID);
if (emitting) {
float restart_phase = float(index) / float(total_particles);
if (randomness > 0.0) {
uint seed = cycle;
if (restart_phase >= system_phase) {
seed -= uint(1);
}
seed *= uint(total_particles);
seed += index;
float random = float(hash(seed) % uint(65536)) / 65536.0;
restart_phase += randomness * random * 1.0 / float(total_particles);
}
restart_phase *= (1.0 - explosiveness);
if (system_phase > prev_system_phase) {
// restart_phase >= prev_system_phase is used so particles emit in the first frame they are processed
if (restart_phase >= prev_system_phase && restart_phase < system_phase) {
restart = true;
if (use_fractional_delta) {
local_delta = (system_phase - restart_phase) * lifetime;
}
}
} else if (delta > 0.0) {
if (restart_phase >= prev_system_phase) {
restart = true;
if (use_fractional_delta) {
local_delta = (1.0 - restart_phase + system_phase) * lifetime;
}
} else if (restart_phase < system_phase) {
restart = true;
if (use_fractional_delta) {
local_delta = (system_phase - restart_phase) * lifetime;
}
}
}
if (restart) {
flags = emitting ? (PARTICLE_FLAG_ACTIVE | PARTICLE_FLAG_STARTED | (cycle << PARTICLE_FRAME_SHIFT)) : 0u;
restart_position = true;
restart_rotation_scale = true;
restart_velocity = true;
restart_color = true;
restart_custom = true;
}
}
bool particle_active = bool(flags & PARTICLE_FLAG_ACTIVE);
uint particle_number = (flags >> PARTICLE_FRAME_SHIFT) * uint(total_particles) + index;
if (restart && particle_active) {
#CODE : START
}
if (particle_active) {
for (uint i = 0u; i < attractor_count; i++) {
vec3 dir;
float amount;
vec3 rel_vec = xform[3].xyz - attractors[i].transform[3].xyz;
vec3 local_pos = rel_vec * mat3(attractors[i].transform);
if (attractors[i].type == ATTRACTOR_TYPE_SPHERE) {
dir = safe_normalize(rel_vec);
float d = length(local_pos) / attractors[i].extents.x;
if (d > 1.0) {
continue;
}
amount = max(0.0, 1.0 - d);
} else if (attractors[i].type == ATTRACTOR_TYPE_BOX) {
dir = safe_normalize(rel_vec);
vec3 abs_pos = abs(local_pos / attractors[i].extents.xyz);
float d = max(abs_pos.x, max(abs_pos.y, abs_pos.z));
if (d > 1.0) {
continue;
}
amount = max(0.0, 1.0 - d);
} else if (attractors[i].type == ATTRACTOR_TYPE_VECTOR_FIELD) {
}
mediump float attractor_attenuation = attractors[i].attenuation;
amount = pow(amount, attractor_attenuation);
dir = safe_normalize(mix(dir, attractors[i].transform[2].xyz, attractors[i].directionality));
attractor_force -= amount * dir * attractors[i].strength;
}
float particle_size = particle_size;
#ifdef USE_COLLISION_SCALE
particle_size *= dot(vec3(length(xform[0].xyz), length(xform[1].xyz), length(xform[2].xyz)), vec3(0.33333333333));
#endif
if (collider_count == 1u && colliders[0].type == COLLIDER_TYPE_2D_SDF) {
//2D collision
vec2 pos = xform[3].xy;
vec4 to_sdf_x = colliders[0].transform[0];
vec4 to_sdf_y = colliders[0].transform[1];
vec2 sdf_pos = vec2(dot(vec4(pos, 0, 1), to_sdf_x), dot(vec4(pos, 0, 1), to_sdf_y));
vec4 sdf_to_screen = vec4(colliders[0].extents.xyz, colliders[0].scale);
vec2 uv_pos = sdf_pos * sdf_to_screen.xy + sdf_to_screen.zw;
if (all(greaterThan(uv_pos, vec2(0.0))) && all(lessThan(uv_pos, vec2(1.0)))) {
vec2 pos2 = pos + vec2(0, particle_size);
vec2 sdf_pos2 = vec2(dot(vec4(pos2, 0, 1), to_sdf_x), dot(vec4(pos2, 0, 1), to_sdf_y));
float sdf_particle_size = distance(sdf_pos, sdf_pos2);
float d = vec4_to_float(texture(height_field_texture, uv_pos)) * SDF_MAX_LENGTH;
// Allowing for a small epsilon to allow particle just touching colliders to count as collided
const float EPSILON = 0.001;
d -= sdf_particle_size;
if (d < EPSILON) {
vec2 n = normalize(vec2(
vec4_to_float(texture(height_field_texture, uv_pos + vec2(EPSILON, 0.0))) - vec4_to_float(texture(height_field_texture, uv_pos - vec2(EPSILON, 0.0))),
vec4_to_float(texture(height_field_texture, uv_pos + vec2(0.0, EPSILON))) - vec4_to_float(texture(height_field_texture, uv_pos - vec2(0.0, EPSILON)))));
collided = true;
sdf_pos2 = sdf_pos + n * d;
pos2 = vec2(dot(vec4(sdf_pos2, 0, 1), colliders[0].transform[2]), dot(vec4(sdf_pos2, 0, 1), colliders[0].transform[3]));
n = pos - pos2;
collision_normal = normalize(vec3(n, 0.0));
collision_depth = length(n);
}
}
} else {
for (uint i = 0u; i < collider_count; i++) {
vec3 normal;
float depth;
bool col = false;
vec3 rel_vec = xform[3].xyz - colliders[i].transform[3].xyz;
vec3 local_pos = rel_vec * mat3(colliders[i].transform);
// Allowing for a small epsilon to allow particle just touching colliders to count as collided
const float EPSILON = 0.001;
if (colliders[i].type == COLLIDER_TYPE_SPHERE) {
float d = length(rel_vec) - (particle_size + colliders[i].extents.x);
if (d < EPSILON) {
col = true;
depth = -d;
normal = normalize(rel_vec);
}
} else if (colliders[i].type == COLLIDER_TYPE_BOX) {
vec3 abs_pos = abs(local_pos);
vec3 sgn_pos = sign(local_pos);
if (any(greaterThan(abs_pos, colliders[i].extents.xyz))) {
//point outside box
vec3 closest = min(abs_pos, colliders[i].extents.xyz);
vec3 rel = abs_pos - closest;
depth = length(rel) - particle_size;
if (depth < EPSILON) {
col = true;
normal = mat3(colliders[i].transform) * (normalize(rel) * sgn_pos);
depth = -depth;
}
} else {
//point inside box
vec3 axis_len = colliders[i].extents.xyz - abs_pos;
// there has to be a faster way to do this?
if (all(lessThan(axis_len.xx, axis_len.yz))) {
normal = vec3(1, 0, 0);
} else if (all(lessThan(axis_len.yy, axis_len.xz))) {
normal = vec3(0, 1, 0);
} else {
normal = vec3(0, 0, 1);
}
col = true;
depth = dot(normal * axis_len, vec3(1)) + particle_size;
normal = mat3(colliders[i].transform) * (normal * sgn_pos);
}
} else if (colliders[i].type == COLLIDER_TYPE_SDF) {
} else if (colliders[i].type == COLLIDER_TYPE_HEIGHT_FIELD) {
vec3 local_pos_bottom = local_pos;
local_pos_bottom.y -= particle_size;
if (any(greaterThan(abs(local_pos_bottom), colliders[i].extents.xyz))) {
continue;
}
const float DELTA = 1.0 / 8192.0;
vec3 uvw_pos = vec3(local_pos_bottom / colliders[i].extents.xyz) * 0.5 + 0.5;
float y = 1.0 - texture(height_field_texture, uvw_pos.xz).r;
if (y + EPSILON > uvw_pos.y) {
//inside heightfield
vec3 pos1 = (vec3(uvw_pos.x, y, uvw_pos.z) * 2.0 - 1.0) * colliders[i].extents.xyz;
vec3 pos2 = (vec3(uvw_pos.x + DELTA, 1.0 - texture(height_field_texture, uvw_pos.xz + vec2(DELTA, 0)).r, uvw_pos.z) * 2.0 - 1.0) * colliders[i].extents.xyz;
vec3 pos3 = (vec3(uvw_pos.x, 1.0 - texture(height_field_texture, uvw_pos.xz + vec2(0, DELTA)).r, uvw_pos.z + DELTA) * 2.0 - 1.0) * colliders[i].extents.xyz;
normal = normalize(cross(pos1 - pos2, pos1 - pos3));
float local_y = (vec3(local_pos / colliders[i].extents.xyz) * 0.5 + 0.5).y;
col = true;
depth = dot(normal, pos1) - dot(normal, local_pos_bottom);
}
}
if (col) {
if (!collided) {
collided = true;
collision_normal = normal;
collision_depth = depth;
} else {
vec3 c = collision_normal * collision_depth;
c += normal * max(0.0, depth - dot(normal, c));
collision_normal = normalize(c);
collision_depth = length(c);
}
}
}
}
}
if (particle_active) {
#CODE : PROCESS
}
flags &= ~PARTICLE_FLAG_ACTIVE;
if (particle_active) {
flags |= PARTICLE_FLAG_ACTIVE;
}
xform = transpose(xform);
out_xform_1 = xform[0];
out_xform_2 = xform[1];
#ifdef MODE_3D
out_xform_3 = xform[2];
#endif
out_velocity_flags.w = uintBitsToFloat(flags);
}
/* clang-format off */
#[fragment]
void main() {
}
/* clang-format on */