From 50c6820cf9182d66fb7eb8e794138b0e7ad27c84 Mon Sep 17 00:00:00 2001
From: Tobias Frisch <tfrisch@uni-koblenz.de>
Date: Sat, 5 Feb 2022 17:05:15 +0100
Subject: [PATCH] Added types of simulations
Signed-off-by: Tobias Frisch <tfrisch@uni-koblenz.de>
---
projects/wobble_bobble/shaders/grid.vert | 16 ++-
projects/wobble_bobble/shaders/particle.inc | 37 ++++++
.../shaders/transform_particles_to_grid.comp | 6 +-
.../shaders/update_particle_velocities.comp | 36 ++++--
projects/wobble_bobble/src/main.cpp | 116 +++++++++++++-----
5 files changed, 160 insertions(+), 51 deletions(-)
diff --git a/projects/wobble_bobble/shaders/grid.vert b/projects/wobble_bobble/shaders/grid.vert
index 3636d87b..54de3f3e 100644
--- a/projects/wobble_bobble/shaders/grid.vert
+++ b/projects/wobble_bobble/shaders/grid.vert
@@ -6,6 +6,10 @@
layout(set=0, binding=0) uniform texture3D gridImage;
layout(set=0, binding=1) uniform sampler gridSampler;
+layout(set=0, binding=2) uniform simulationBlock {
+ Simulation simulation;
+};
+
layout(location = 0) in vec2 vertexPos;
layout(location = 0) out vec2 passPos;
@@ -32,13 +36,17 @@ void main() {
gridID = actual_mod(gridID, gridResolution);
vec3 position = (vec3(gridID) + vec3(0.5f)) / gridResolution;
- float size = 1.0f / length(vec3(gridResolution));
+
+ vec3 size = vec3(1.0f) / vec3(gridResolution);
+ float volume = size.x * size.y * size.z;
+ float radius = cube_radius(volume);
vec4 gridData = texture(sampler3D(gridImage, gridSampler), position);
float mass = gridData.w;
- float density = mass / sphere_volume(size);
- float alpha = clamp(density / 10000.0f, 0.0f, 1.0f);
+ float density = mass / volume;
+
+ float alpha = clamp(density / simulation.density, 0.0f, 1.0f);
passPos = vertexPos;
passVelocity = gridData.xyz;
@@ -46,5 +54,5 @@ void main() {
// align voxel to face camera
gl_Position = mvp * vec4(position, 1); // transform position into projected view space
- gl_Position.xy += vertexPos * mix(0.0f, size * 2.0f, alpha); // move position directly in view space
+ gl_Position.xy += vertexPos * (radius * 2.0f) * alpha; // move position directly in view space
}
\ No newline at end of file
diff --git a/projects/wobble_bobble/shaders/particle.inc b/projects/wobble_bobble/shaders/particle.inc
index 72791f9a..266e5e01 100644
--- a/projects/wobble_bobble/shaders/particle.inc
+++ b/projects/wobble_bobble/shaders/particle.inc
@@ -19,6 +19,24 @@ struct Particle {
mat4 mls;
};
+#define SIM_FORM_SPHERE 0
+#define SIM_FORM_CUBE 1
+
+#define SIM_TYPE_HYPERELASTIC 0
+#define SIM_TYPE_FLUID 1
+
+struct Simulation {
+ float density;
+ float size;
+ float lame1;
+ float lame2;
+ int form;
+ int type;
+ float K;
+ float E;
+ float gamma;
+};
+
const float PI = 3.1415926535897932384626433832795;
float sphere_volume(float radius) {
@@ -29,6 +47,25 @@ float sphere_radius(float volume) {
return pow(volume * 3.0f / 4.0f / PI, 1.0f / 3.0f);
}
+float cube_volume(float radius) {
+ return 8.0f * (radius * radius * radius);
+}
+
+float cube_radius(float volume) {
+ return pow(volume / 8.0f, 1.0f / 3.0f);
+}
+
+float simulationMass(float density, float size, int form) {
+ switch (form) {
+ case SIM_FORM_SPHERE:
+ return density * sphere_volume(size);
+ case SIM_FORM_CUBE:
+ return density * cube_volume(size);
+ default:
+ return 0.0f;
+ }
+}
+
float weight_A(float x) {
return max(1.0f - x, 0.0f);
}
diff --git a/projects/wobble_bobble/shaders/transform_particles_to_grid.comp b/projects/wobble_bobble/shaders/transform_particles_to_grid.comp
index 1bcea69d..236ff763 100644
--- a/projects/wobble_bobble/shaders/transform_particles_to_grid.comp
+++ b/projects/wobble_bobble/shaders/transform_particles_to_grid.comp
@@ -12,8 +12,6 @@ layout(set=0, binding=0, std430) readonly buffer particleBuffer {
layout(set=0, binding=1, rgba32f) restrict writeonly uniform image3D gridImage;
layout( push_constant ) uniform constants {
- float lame1;
- float lame2;
float t;
float dt;
float speedfactor;
@@ -71,6 +69,10 @@ void main() {
memoryBarrierShared();
}
+ if (any(isnan(gridValue.xyz)) || any(isinf(gridValue.xyz))) {
+ gridValue.xyz = vec3(0.0f);
+ }
+
gridValue.xyz += vec3(0.0f, -9.81f * dts * gridValue.w, 0.0f);
bvec3 lowerID = lessThanEqual(gl_GlobalInvocationID, ivec3(0));
diff --git a/projects/wobble_bobble/shaders/update_particle_velocities.comp b/projects/wobble_bobble/shaders/update_particle_velocities.comp
index cba521a5..60b5a72e 100644
--- a/projects/wobble_bobble/shaders/update_particle_velocities.comp
+++ b/projects/wobble_bobble/shaders/update_particle_velocities.comp
@@ -10,12 +10,14 @@ layout(set=0, binding=0, std430) restrict buffer particleBuffer {
Particle particles [];
};
-layout(set=0, binding=1) uniform texture3D gridImage;
-layout(set=0, binding=2) uniform sampler gridSampler;
+layout(set=0, binding=1) uniform simulationBlock {
+ Simulation simulation;
+};
+
+layout(set=0, binding=2) uniform texture3D gridImage;
+layout(set=0, binding=3) uniform sampler gridSampler;
layout( push_constant ) uniform constants {
- float lame1;
- float lame2;
float t;
float dt;
float speedfactor;
@@ -86,18 +88,30 @@ void main() {
}
float J = max(determinant(F), EPSILON);
-
float volume = sphere_volume(size);
- mat3 F_T = transpose(F);
- mat3 F_T_inv = inverse(F_T);
+ mat3 stress = mat3(0.0f);
- mat3 P_term_0 = lame2 * (F - F_T_inv);
- mat3 P_term_1 = lame1 * log(J) * F_T_inv;
+ switch (simulation.type) {
+ case SIM_TYPE_HYPERELASTIC:
+ mat3 F_T = transpose(F);
+ mat3 F_T_inv = inverse(F_T);
- mat3 P = P_term_0 + P_term_1;
+ mat3 P_term_0 = simulation.lame2 * (F - F_T_inv);
+ mat3 P_term_1 = simulation.lame1 * log(J) * F_T_inv;
- mat3 stress = P * F_T;
+ mat3 P = P_term_0 + P_term_1;
+
+ stress = P * F_T;
+ break;
+ case SIM_TYPE_FLUID:
+ float pressure = simulation.K * (1.0f / pow(J, simulation.gamma) - 1.0f);
+
+ stress = mat3(-pressure * J);
+ break;
+ default:
+ break;
+ }
mls_Q -= dts * volume * stress * D_inv;
diff --git a/projects/wobble_bobble/src/main.cpp b/projects/wobble_bobble/src/main.cpp
index 5fabe497..117a7cf9 100644
--- a/projects/wobble_bobble/src/main.cpp
+++ b/projects/wobble_bobble/src/main.cpp
@@ -19,9 +19,25 @@ struct Particle {
glm::mat4 mls;
};
-struct Physics {
+#define SIM_FORM_SPHERE 0
+#define SIM_FORM_CUBE 1
+
+#define SIM_TYPE_HYPERELASTIC 0
+#define SIM_TYPE_FLUID 1
+
+struct Simulation {
+ float density;
+ float size;
float lame1;
- float lame2;
+ float lame2;
+ int form;
+ int type;
+ float K;
+ float E;
+ float gamma;
+};
+
+struct Physics {
float t;
float dt;
float speedfactor;
@@ -170,17 +186,33 @@ vkcv::ComputePipelineHandle createComputePipeline(vkcv::Core& core, vkcv::shader
}
void resetParticles(vkcv::Buffer<Particle>& particles, const glm::vec3& velocity,
- float density, float size) {
+ float density, float size, int form) {
std::vector<Particle> particles_vec (particles.getCount());
- distributeParticlesCube(
- particles_vec.data(),
- particles_vec.size(),
- glm::vec3(0.5f),
- size,
- density * sphere_volume(size),
- velocity
- );
+ switch (form) {
+ case SIM_FORM_SPHERE:
+ distributeParticlesSphere(
+ particles_vec.data(),
+ particles_vec.size(),
+ glm::vec3(0.5f),
+ size,
+ density * sphere_volume(size),
+ velocity
+ );
+ break;
+ case SIM_FORM_CUBE:
+ distributeParticlesCube(
+ particles_vec.data(),
+ particles_vec.size(),
+ glm::vec3(0.5f),
+ size,
+ density * sphere_volume(size),
+ velocity
+ );
+ break;
+ default:
+ break;
+ }
particles.fill(particles_vec);
}
@@ -217,18 +249,12 @@ int main(int argc, const char **argv) {
swapchainExtent.width,
swapchainExtent.height
).getHandle();
-
- glm::vec3 initialVelocity (0.0f, 0.1f, 0.0f);
- float density = 2500.0f;
- float radius = 0.1f;
vkcv::Buffer<Particle> particles = core.createBuffer<Particle>(
vkcv::BufferType::STORAGE,
1024
);
- resetParticles(particles, initialVelocity, density, radius);
-
vkcv::Image grid = core.createImage(
vk::Format::eR32G32B32A32Sfloat,
64,
@@ -255,6 +281,26 @@ int main(int argc, const char **argv) {
vkcv::SamplerBorderColor::FLOAT_ZERO_TRANSPARENT
);
+ vkcv::Buffer<Simulation> simulation = core.createBuffer<Simulation>(
+ vkcv::BufferType::UNIFORM, 1, vkcv::BufferMemoryType::HOST_VISIBLE
+ );
+
+ Simulation* sim = simulation.map();
+
+ glm::vec3 initialVelocity (0.0f, 0.1f, 0.0f);
+
+ sim->density = 2500.0f;
+ sim->size = 0.1f;
+ sim->lame1 = 10.0f;
+ sim->lame2 = 20.0f;
+ sim->form = SIM_FORM_SPHERE;
+ sim->type = SIM_TYPE_HYPERELASTIC;
+ sim->K = 2.2f;
+ sim->E = 35.0f;
+ sim->gamma = 1.330f;
+
+ resetParticles(particles, initialVelocity, sim->density, sim->size, sim->form);
+
vkcv::shader::GLSLCompiler compiler;
std::vector<vkcv::DescriptorSetHandle> initParticleWeightsSets;
@@ -296,8 +342,9 @@ int main(int argc, const char **argv) {
{
vkcv::DescriptorWrites writes;
writes.storageBufferWrites.push_back(vkcv::BufferDescriptorWrite(0, particles.getHandle()));
- writes.sampledImageWrites.push_back(vkcv::SampledImageDescriptorWrite(1, grid.getHandle()));
- writes.samplerWrites.push_back(vkcv::SamplerDescriptorWrite(2, gridSampler));
+ writes.uniformBufferWrites.push_back(vkcv::BufferDescriptorWrite(1, simulation.getHandle()));
+ writes.sampledImageWrites.push_back(vkcv::SampledImageDescriptorWrite(2, grid.getHandle()));
+ writes.samplerWrites.push_back(vkcv::SamplerDescriptorWrite(3, gridSampler));
core.writeDescriptorSet(updateParticleVelocitiesSets[0], writes);
}
@@ -404,6 +451,7 @@ int main(int argc, const char **argv) {
vkcv::DescriptorWrites writes;
writes.sampledImageWrites.push_back(vkcv::SampledImageDescriptorWrite(0, grid.getHandle()));
writes.samplerWrites.push_back(vkcv::SamplerDescriptorWrite(1, gridSampler));
+ writes.uniformBufferWrites.push_back(vkcv::BufferDescriptorWrite(2, simulation.getHandle()));
core.writeDescriptorSet(gfxSetGrid, writes);
}
@@ -435,7 +483,6 @@ int main(int argc, const char **argv) {
gfxPipelineConfigGrid.m_VertexLayout = vertexLayoutGrid;
gfxPipelineConfigGrid.m_DescriptorLayouts = { gfxSetLayoutGrid };
gfxPipelineConfigGrid.m_UseDynamicViewport = true;
- gfxPipelineConfigGrid.m_blendMode = vkcv::BlendMode::Additive;
vkcv::VertexLayout vertexLayoutParticles ({
vkcv::VertexBinding(0, gfxProgramParticles.getVertexAttachments())
@@ -548,8 +595,6 @@ int main(int argc, const char **argv) {
bool renderGrid = true;
- float lame1 = 10.0f;
- float lame2 = 20.0f;
float speed_factor = 1.0f;
auto start = std::chrono::system_clock::now();
@@ -585,8 +630,6 @@ int main(int argc, const char **argv) {
current = next;
Physics physics;
- physics.lame1 = lame1;
- physics.lame2 = lame2;
physics.t = static_cast<float>(0.000001 * static_cast<double>(time.count()));
physics.dt = static_cast<float>(0.000001 * static_cast<double>(deltatime.count()));
physics.speedfactor = speed_factor;
@@ -642,6 +685,7 @@ int main(int argc, const char **argv) {
core.recordBeginDebugLabel(cmdStream, "UPDATE PARTICLE VELOCITIES", {0.78f, 0.89f, 0.94f, 1.0f});
core.recordBufferMemoryBarrier(cmdStream, particles.getHandle());
+ core.recordBufferMemoryBarrier(cmdStream, simulation.getHandle());
core.prepareImageForSampling(cmdStream, grid.getHandle());
core.recordComputeDispatchToCmdStream(
@@ -665,6 +709,7 @@ int main(int argc, const char **argv) {
if (renderGrid) {
core.recordBeginDebugLabel(cmdStream, "RENDER GRID", { 0.13f, 0.20f, 0.22f, 1.0f });
+ core.recordBufferMemoryBarrier(cmdStream, simulation.getHandle());
core.prepareImageForSampling(cmdStream, grid.getHandle());
core.recordDrawcallsToCmdStream(
@@ -714,25 +759,27 @@ int main(int argc, const char **argv) {
gui.beginGUI();
ImGui::Begin("Settings");
+
+ ImGui::Combo("Type", &(sim->type), "Hyperelastic\0Fluid", 2);
- ImGui::SliderFloat("Density", &density, std::numeric_limits<float>::epsilon(), 5000.0f);
+ ImGui::SliderFloat("Density", &(sim->density), std::numeric_limits<float>::epsilon(), 5000.0f);
ImGui::SameLine(0.0f, 10.0f);
if (ImGui::SmallButton("Reset##density")) {
- density = 2500.0f;
+ sim->density = 2500.0f;
}
- ImGui::SliderFloat("Radius", &radius, 0.0f, 0.5f);
+ ImGui::SliderFloat("Radius", &(sim->size), 0.0f, 0.5f);
ImGui::SameLine(0.0f, 10.0f);
if (ImGui::SmallButton("Reset##radius")) {
- radius = 0.1f;
+ sim->size = 0.1f;
}
-
- ImGui::BeginGroup();
- ImGui::SliderFloat("Compression Modulus", &lame1, 0.0f, 100.0f);
- ImGui::EndGroup();
ImGui::BeginGroup();
- ImGui::SliderFloat("Elasticity Modulus", &lame2, 0.0f, 100.0f);
+ ImGui::SliderFloat("Bulk Modulus", &(sim->K), 0.0f, 100.0f);
+ ImGui::SliderFloat("Young's Modulus", &(sim->E), 0.0f, 100.0f);
+ ImGui::SliderFloat("Heat Capacity Ratio", &(sim->gamma), 1.0f, 2.0f);
+ ImGui::SliderFloat("Lame1", &(sim->lame1), 0.0f, 100.0f);
+ ImGui::SliderFloat("Lame2", &(sim->lame2), 0.0f, 100.0f);
ImGui::EndGroup();
ImGui::Spacing();
@@ -745,7 +792,7 @@ int main(int argc, const char **argv) {
ImGui::DragFloat3("Initial Velocity", reinterpret_cast<float*>(&initialVelocity), 0.001f);
ImGui::SameLine(0.0f, 10.0f);
if (ImGui::Button("Reset##particle_velocity")) {
- resetParticles(particles, initialVelocity, density, radius);
+ resetParticles(particles, initialVelocity, sim->density, sim->size, sim->form);
}
ImGui::End();
@@ -754,5 +801,6 @@ int main(int argc, const char **argv) {
core.endFrame(windowHandle);
}
+ simulation.unmap();
return 0;
}
--
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