diff --git a/include/vkcv/PipelineConfig.hpp b/include/vkcv/PipelineConfig.hpp
index 1e00c5209118469a7dc6ff1eb1e3c98a3c6903a7..45539769e38d447cf6f283e6e9d2cdcbc9d78c22 100644
--- a/include/vkcv/PipelineConfig.hpp
+++ b/include/vkcv/PipelineConfig.hpp
@@ -15,6 +15,10 @@ namespace vkcv {
enum class PrimitiveTopology{PointList, LineList, TriangleList };
+ // add more as needed
+ // alternatively we could expose the blend factors directly
+ enum class BlendMode{ None, Additive };
+
struct PipelineConfig {
ShaderProgram m_ShaderProgram;
uint32_t m_Width;
@@ -25,6 +29,7 @@ namespace vkcv {
bool m_UseDynamicViewport;
bool m_UseConservativeRasterization = false;
PrimitiveTopology m_PrimitiveTopology = PrimitiveTopology::TriangleList;
+ BlendMode m_blendMode = BlendMode::None;
};
}
\ No newline at end of file
diff --git a/projects/particle_simulation/shaders/frag_space.spv b/projects/particle_simulation/shaders/frag_space.spv
index f05bab5cddababb06332586007586fee842e51c2..8acf8a4295ba661f1b7a893d3c8dd508a4b168b6 100644
Binary files a/projects/particle_simulation/shaders/frag_space.spv and b/projects/particle_simulation/shaders/frag_space.spv differ
diff --git a/projects/particle_simulation/shaders/frag_water.spv b/projects/particle_simulation/shaders/frag_water.spv
index 0ce71df61bc127c7d057d290b78871593ee4f78e..406e44df35757621d0688d37bd93cb83f5f04c24 100644
Binary files a/projects/particle_simulation/shaders/frag_water.spv and b/projects/particle_simulation/shaders/frag_water.spv differ
diff --git a/projects/particle_simulation/shaders/particleShading.inc b/projects/particle_simulation/shaders/particleShading.inc
new file mode 100644
index 0000000000000000000000000000000000000000..b2d1832b9ccd6ba05a585b59bdfdedd4729e80f8
--- /dev/null
+++ b/projects/particle_simulation/shaders/particleShading.inc
@@ -0,0 +1,6 @@
+float circleFactor(vec2 triangleCoordinates){
+ // percentage of distance from center to circle edge
+ float p = clamp((0.4 - length(triangleCoordinates)) / 0.4, 0, 1);
+ // remapping for nice falloff
+ return sqrt(p);
+}
\ No newline at end of file
diff --git a/projects/particle_simulation/shaders/shader.vert b/projects/particle_simulation/shaders/shader.vert
index 7884d09462c96027fbcec8c2d1f36a2b26a4e6d5..ad80a4e109ebdc71848221b23a6292f1fe8425b4 100644
--- a/projects/particle_simulation/shaders/shader.vert
+++ b/projects/particle_simulation/shaders/shader.vert
@@ -23,6 +23,7 @@ layout( push_constant ) uniform constants{
mat4 projection;
};
+layout(location = 0) out vec2 passTriangleCoordinates;
layout(location = 1) out vec3 passVelocity;
layout(location = 2) out float passlifeTime;
@@ -36,5 +37,9 @@ void main()
// by adding the triangle position in view space the mesh is always camera facing
positionView.xyz += particle;
// multiply with projection matrix for final position
- gl_Position = projection * positionView;
+ gl_Position = projection * positionView;
+
+ // 0.01 corresponds to vertex position size in main
+ float normalizationDivider = 0.01;
+ passTriangleCoordinates = particle.xy / normalizationDivider;
}
\ No newline at end of file
diff --git a/projects/particle_simulation/shaders/shader_space.frag b/projects/particle_simulation/shaders/shader_space.frag
index 79c80c3befd377726f4c5c686d420535ed518123..a1da54038381e142f0d40de8c3314514fa37f543 100644
--- a/projects/particle_simulation/shaders/shader_space.frag
+++ b/projects/particle_simulation/shaders/shader_space.frag
@@ -1,6 +1,10 @@
#version 450
#extension GL_ARB_separate_shader_objects : enable
+#extension GL_GOOGLE_include_directive : enable
+#include "particleShading.inc"
+
+layout(location = 0) in vec2 passTriangleCoordinates;
layout(location = 1) in vec3 passVelocity;
layout(location = 2) in float passlifeTime;
@@ -14,6 +18,7 @@ layout(set=0,binding=1) uniform uPosition{
vec2 position;
} Position;
+
void main()
{
vec2 mouse = vec2(Position.position.x, Position.position.y);
@@ -21,4 +26,9 @@ void main()
float(passlifeTime < 2 && passlifeTime > 1) * vec4(1,passlifeTime * 0.5,0,0) +
float(passlifeTime >= 2 && passlifeTime < 2.5f) * vec4(passlifeTime * 0.5,passlifeTime * 0.5,0,0) +
float(passlifeTime >= 2.5f) * vec4(1,0,0,0);
+
+ // make the triangle look like a circle
+ outColor *= circleFactor(passTriangleCoordinates);
+ // full color is achieved by additively blending many particles
+ outColor *= 0.5;
}
\ No newline at end of file
diff --git a/projects/particle_simulation/shaders/shader_water.frag b/projects/particle_simulation/shaders/shader_water.frag
index 3f817c1c0b4d759742a47481db6590349aea73f4..b0b4cc7050523d52fee25eb46401a9d32f67331d 100644
--- a/projects/particle_simulation/shaders/shader_water.frag
+++ b/projects/particle_simulation/shaders/shader_water.frag
@@ -1,6 +1,10 @@
#version 450
#extension GL_ARB_separate_shader_objects : enable
+#extension GL_GOOGLE_include_directive : enable
+#include "particleShading.inc"
+
+layout(location = 0) in vec2 passTriangleCoordinates;
layout(location = 1) in vec3 passVelocity;
layout(location = 2) in float passlifeTime;
@@ -22,4 +26,9 @@ void main()
float(passlifeTime < 2 && passlifeTime > 1) * vec4(0.3, 0.7,1,0) +
float(passlifeTime >= 2 && passlifeTime < 4.f) * vec4(0.5,0.9,1,0) +
float(passlifeTime >= 4.f) * vec4(0.9,1,1,0);
+
+ // make the triangle look like a circle
+ outColor *= circleFactor(passTriangleCoordinates);
+ // full color is achieved by additively blending many particles
+ outColor *= 0.5;
}
diff --git a/projects/particle_simulation/shaders/vert.spv b/projects/particle_simulation/shaders/vert.spv
index 0387f48623f02789d7b0cce0a06128996c0b3cb6..e5a23d663612f70bbbafca156f9a49215dc2fd72 100644
Binary files a/projects/particle_simulation/shaders/vert.spv and b/projects/particle_simulation/shaders/vert.spv differ
diff --git a/projects/particle_simulation/src/main.cpp b/projects/particle_simulation/src/main.cpp
index f26080368427a668db9e226d9fd8c99164bb235d..b2eb5bc59581795502c0b7df0ed63eca57df01d6 100644
--- a/projects/particle_simulation/src/main.cpp
+++ b/projects/particle_simulation/src/main.cpp
@@ -95,7 +95,7 @@ int main(int argc, const char **argv) {
const vkcv::VertexLayout particleLayout(bindings);
- const vkcv::PipelineConfig particlePipelineDefinition{
+ vkcv::PipelineConfig particlePipelineDefinition{
particleShaderProgram,
UINT32_MAX,
UINT32_MAX,
@@ -103,10 +103,11 @@ int main(int argc, const char **argv) {
{particleLayout},
{core.getDescriptorSet(descriptorSet).layout},
true};
+ particlePipelineDefinition.m_blendMode = vkcv::BlendMode::Additive;
- const std::vector<glm::vec3> vertices = {glm::vec3(-0.005, 0.005, 0),
- glm::vec3(0.005, 0.005, 0),
- glm::vec3(0, -0.005, 0)};
+ const std::vector<glm::vec3> vertices = {glm::vec3(-0.01, 0.01, 0),
+ glm::vec3(0.01, 0.01, 0),
+ glm::vec3(0, -0.01, 0)};
vertexBuffer.fill(vertices);
diff --git a/src/vkcv/PipelineManager.cpp b/src/vkcv/PipelineManager.cpp
index df36442efc2992bf16b6e82245ef9753dad95e5d..47694ab610e3af3a21b3781c8eb2ccd278a06afc 100644
--- a/src/vkcv/PipelineManager.cpp
+++ b/src/vkcv/PipelineManager.cpp
@@ -182,8 +182,11 @@ namespace vkcv
VK_COLOR_COMPONENT_G_BIT |
VK_COLOR_COMPONENT_B_BIT |
VK_COLOR_COMPONENT_A_BIT);
+
+ // currently set to additive, if not disabled
+ // BlendFactors must be set as soon as additional BlendModes are added
vk::PipelineColorBlendAttachmentState colorBlendAttachmentState(
- false,
+ config.m_blendMode != BlendMode::None,
vk::BlendFactor::eOne,
vk::BlendFactor::eOne,
vk::BlendOp::eAdd,