Bind key to reset lattice buffers

i.e. restarting the simulation without clearing the geometry

6 files changed, 42 insertions, 29 deletions

diff --git a/src/buffer/vertex/fluid_cell_buffer.cc b/src/buffer/vertex/fluid_cell_buffer.cc
index 4930d63..8fdc579 100644
--- a/src/buffer/vertex/fluid_cell_buffer.cc
+++ b/src/buffer/vertex/fluid_cell_buffer.cc
@@ -4,17 +4,27 @@
 
 FluidCellBuffer::FluidCellBuffer(GLuint nX, GLuint nY, std::function<int(int,int)>&& geometry):
 	_nX(nX), _nY(nY) {
-	glGenVertexArrays(1, &_array);
 	glGenBuffers(1, &_buffer);
-
 	glBindVertexArray(_array);
+	init(std::forward<decltype(geometry)>(geometry));
+	glEnableVertexAttribArray(0);
+	glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 0, nullptr);
+
+}
+
+FluidCellBuffer::~FluidCellBuffer() {
+	glDeleteBuffers(1, &_buffer);
+	glDeleteVertexArrays(1, &_array);
+}
+
+void FluidCellBuffer::init(std::function<int(int,int)>&& geometry) {
 	glBindBuffer(GL_ARRAY_BUFFER, _buffer);
 
-	std::vector<GLfloat> data(3*nX*nY, GLfloat{});
+	std::vector<GLfloat> data(3*_nX*_nY, GLfloat{});
 
-	for ( int x = 0; x < nX; ++x ) {
-		for ( int y = 0; y < nY; ++y ) {
-			data[3*nX*y + 3*x + 2] = geometry(x,y);
+	for ( int x = 0; x < _nX; ++x ) {
+		for ( int y = 0; y < _nY; ++y ) {
+			data[3*_nX*y + 3*x + 2] = geometry(x,y);
 		}
 	}
 
@@ -24,14 +34,6 @@ FluidCellBuffer::FluidCellBuffer(GLuint nX, GLuint nY, std::function<int(int,int
 		data.data(),
 		GL_DYNAMIC_DRAW
 	);
-
-	glEnableVertexAttribArray(0);
-	glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 0, nullptr);
-}
-
-FluidCellBuffer::~FluidCellBuffer() {
-	glDeleteBuffers(1, &_buffer);
-	glDeleteVertexArrays(1, &_array);
 }
 
 GLuint FluidCellBuffer::getBuffer() const {
diff --git a/src/buffer/vertex/fluid_cell_buffer.h b/src/buffer/vertex/fluid_cell_buffer.h
index 8afb342..791ebea 100644
--- a/src/buffer/vertex/fluid_cell_buffer.h
+++ b/src/buffer/vertex/fluid_cell_buffer.h
@@ -16,6 +16,8 @@ public:
 	FluidCellBuffer(GLuint nX, GLuint nY, std::function<int(int,int)>&& geometry);
 	~FluidCellBuffer();
 
+	void init(std::function<int(int,int)>&& geometry);
+
 	GLuint getBuffer() const;
 
 	void draw() const;
diff --git a/src/buffer/vertex/lattice_cell_buffer.cc b/src/buffer/vertex/lattice_cell_buffer.cc
index 2011b14..f3ef47d 100644
--- a/src/buffer/vertex/lattice_cell_buffer.cc
+++ b/src/buffer/vertex/lattice_cell_buffer.cc
@@ -20,13 +20,15 @@ std::vector<GLfloat> makeLattice(GLuint nX, GLuint nY) {
 	return data;
 }
 
-LatticeCellBuffer::LatticeCellBuffer(GLuint nX, GLuint nY) {
-	glGenVertexArrays(1, &_array);
+LatticeCellBuffer::LatticeCellBuffer(GLuint nX, GLuint nY):
+	_nX(nX), _nY(nY) {
 	glGenBuffers(1, &_buffer);
+	init();
+}
 
-	const std::vector<GLfloat> data = makeLattice(nX, nY);
+void LatticeCellBuffer::init() {
+	const std::vector<GLfloat> data = makeLattice(_nX, _nY);
 
-	glBindVertexArray(_array);
 	glBindBuffer(GL_ARRAY_BUFFER, _buffer);
 	glBufferData(
 		GL_ARRAY_BUFFER,
@@ -34,14 +36,10 @@ LatticeCellBuffer::LatticeCellBuffer(GLuint nX, GLuint nY) {
 		data.data(),
 		GL_DYNAMIC_DRAW
 	);
-
-	glEnableVertexAttribArray(0);
-	glVertexAttribPointer(0, 1, GL_FLOAT, GL_FALSE, 0, nullptr);
 }
 
 LatticeCellBuffer::~LatticeCellBuffer() {
 	glDeleteBuffers(1, &_buffer);
-	glDeleteVertexArrays(1, &_array);
 }
 
 GLuint LatticeCellBuffer::getBuffer() const {
diff --git a/src/buffer/vertex/lattice_cell_buffer.h b/src/buffer/vertex/lattice_cell_buffer.h
index e5e00a4..cabff67 100644
--- a/src/buffer/vertex/lattice_cell_buffer.h
+++ b/src/buffer/vertex/lattice_cell_buffer.h
@@ -4,6 +4,8 @@
 
 class LatticeCellBuffer {
 private:
+	GLuint _nX;
+	GLuint _nY;
 	GLuint _array;
 	GLuint _buffer;
 
@@ -11,5 +13,7 @@ public:
 	LatticeCellBuffer(GLuint nX, GLuint nY);
 	~LatticeCellBuffer();
 
+	void init();
+
 	GLuint getBuffer() const;
 };
diff --git a/src/main.cc b/src/main.cc
index c69bbe1..f3f14ec 100644
--- a/src/main.cc
+++ b/src/main.cc
@@ -105,6 +105,8 @@ int render() {
 		return -1;
 	}
 
+	auto reset_key = window.getKeyWatcher(GLFW_KEY_R);
+
 	auto pause_key  = window.getKeyWatcher(GLFW_KEY_SPACE);
 	bool update_lattice = true;
 
@@ -135,6 +137,11 @@ int render() {
 	bool tick = true;
 
 	window.render([&](bool window_size_changed) {
+		if ( reset_key.wasClicked() ) {
+			iT = 0;
+			lattice_a->init();
+			lattice_b->init();
+		}
 		if ( pause_key.wasClicked() ) {
 			update_lattice = !update_lattice;
 		}
diff --git a/src/shader/code/collide.glsl b/src/shader/code/collide.glsl
index d877634..e2c3212 100644
--- a/src/shader/code/collide.glsl
+++ b/src/shader/code/collide.glsl
@@ -13,13 +13,6 @@ uniform uint iT;
 
 uniform bool show_fluid_quality;
 
-/// Fluid characteristics
-
-const float physCharLength   = 1.0;
-const float physCharVelocity = 1.0;
-const float physViscosity    = 0.01;
-const float latticeCharVelocity = 0.01;
-
 /// LBM constants
 
 const uint  q         = 9;
@@ -30,6 +23,13 @@ const float weight[q] = float[](
 );
 const float invCs2 = 1./3.;
 
+/// Fluid characteristics
+
+const float physCharLength   = 1.0;
+const float physCharVelocity = 1.0;
+const float physViscosity    = 0.01;
+const float latticeCharVelocity = 0.1;
+
 /// Unit conversion
 
 const float resolution    = max(nX,nY);