Corrected update of deformation with dt

Signed-off-by: Tobias Frisch <tfrisch@uni-koblenz.de>

projects/wobble_bobble/shaders/init_particle_volumes.comp

@@ -43,10 +43,14 @@ void main()	{
         }
 
         if (volume > 0.0f) {
+            float density = minimal.mass / volume;
+
             //volume = minimal.mass / (mass / volume);
+            mass = density * volume;
         }
 
         particles[gl_GlobalInvocationID.x].minimal.size = sphere_radius(volume);
+        particles[gl_GlobalInvocationID.x].minimal.mass = mass;
     }
 
     memoryBarrierBuffer();

projects/wobble_bobble/shaders/particle.inc

@@ -113,7 +113,7 @@ vec3 voxel_particle_grad_weight(vec3 voxel, ParticleMinimal particle) {
 		grad_weight_C(delta.x),
 		grad_weight_C(delta.y),
 		grad_weight_C(delta.z)
-	) * sign;
+	) * sign / particle.size;
 	
 	return vec3(
 			grad_weight.x * weight.y * weight.z,

projects/wobble_bobble/shaders/update_particle_deformation.comp

@@ -12,6 +12,13 @@ layout(set=0, binding=0, std430) buffer particleBuffer {
 layout(set=0, binding=1) uniform texture3D gridImage;
 layout(set=0, binding=2) uniform sampler gridSampler;
 
+layout( push_constant ) uniform constants {
+    float K;
+    float E;
+    float t;
+    float dt;
+};
+
 void main()	{
     memoryBarrierBuffer();
     memoryBarrierImage();
@@ -45,7 +52,11 @@ void main()	{
             }
         }
 
-        mat3 deformation_elastic = (mat3(1.0f) + velocity_gradient) * deformation;
+        mat3 deformation_elastic = deformation;
+
+        if (dt > 0.0f) {
+            deformation_elastic = (mat3(1.0f) + dt * velocity_gradient) * deformation;
+        }
 
         particles[gl_GlobalInvocationID.x].deformation = mat4(deformation_elastic);
     }

projects/wobble_bobble/src/main.cpp

@@ -688,7 +688,7 @@ int main(int argc, const char **argv) {
 				{ vkcv::DescriptorSetUsage(
 						0, core.getDescriptorSet(updateParticleDeformationSets[0]).vulkanHandle
 				) },
-				vkcv::PushConstants(0)
+				physicsPushConstants
 		);
 		
 		core.recordBufferMemoryBarrier(cmdStream, particles.getHandle());