minor optimizations

shaders/fragment.glsl

@@ -4,10 +4,10 @@ out vec4 FragColor;
 
 in vec3 color;
 
-uniform bool drawPoints = false;
+uniform bool drawPoints;
 
 void main() {
-    if (drawPoints == true){
+    if (drawPoints){
         vec2 coord = gl_PointCoord - vec2(0.5);
         if (length(coord) > 0.5)
             discard;

shaders/vertex.glsl

@@ -6,7 +6,7 @@ layout (location = 2) in float vMassRadius;
 
 uniform mat3 VP;
 
-uniform bool drawPoints = false;
+uniform bool drawPoints;
 uniform float screenSizePixels;
 uniform float screenSizeMeters;
 uniform float depthOffset;
@@ -14,12 +14,11 @@ uniform float depthOffset;
 out vec3 color;
 
 void main() {
-    if (drawPoints == true){
-        gl_Position = vec4(VP * vPos, 1.0);
+    gl_Position = vec4(VP * vPos, 1.0);
+    if (drawPoints){
         gl_Position.z -= depthOffset * 0.5;
         gl_PointSize = vMassRadius / screenSizeMeters * screenSizePixels * 2;
     } else {
-        gl_Position = vec4(VP * vPos, 1.0);
         color = vColor;
     }
 }

src/GLWidget.cpp

@@ -13,7 +13,7 @@ GLWidget::GLWidget(Simulation * simulation) : simulation(simulation) {
 	startTimer(1000 / 144);
 	fps = new FPS;
 	fps->setUpdateInterval(500);
-	connect(simulation, &Simulation::layoutChanged, this, &GLWidget::initGPUMemory);
+	connect(simulation, &Simulation::layoutChanged, this, &GLWidget::uploadStaticDataToGPU);
 	connect(simulation, &Simulation::positionChanged, this, &GLWidget::changePosition);
 }
 
@@ -41,13 +41,10 @@ void GLWidget::initializeGL() {
 	glClearColor(.15, .15, .15, 1);
 
 	std::vector<Pendulum*> empty;
-	initGPUMemory(&empty);
+	uploadStaticDataToGPU(&empty);
 }
 
 void GLWidget::paintGL() {
-	QPixmap img(size());
-	auto p = new QPainter(&img);
-
 	// Native OpenGL
 	{
 
@@ -76,6 +73,8 @@ void GLWidget::paintGL() {
 		glBindVertexArray(0);
 	}
 
+	QPixmap img(size());
+	auto p = new QPainter(&img);
 	// FPS
 	{
 		p->setPen(Qt::white);
@@ -102,7 +101,7 @@ bool GLWidget::AnyDialogOpen() {
 	return false;
 }
 
-void GLWidget::initGPUMemory(const std::vector<Pendulum *> *pendula) {
+void GLWidget::uploadStaticDataToGPU(const std::vector<Pendulum *> *pendula) {
 
 	int pointCount = std::transform_reduce(pendula->begin(), pendula->end(), 0, [](int prev, int curr){
 		return prev + curr + 1;
@@ -183,29 +182,23 @@ void GLWidget::initGPUMemory(const std::vector<Pendulum *> *pendula) {
 
 	glBindVertexArray(0);
 
-	glBindBuffer(GL_ARRAY_BUFFER, 0);
-	glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
-
 	simulation->pendulaMutex.unlock();
 }
 
 void GLWidget::changePosition(const std::vector<Pendulum *> *pendula) {
 	glBindBuffer(GL_ARRAY_BUFFER, positionVBO);
 	auto positions = (GLfloat*) glMapBufferRange(GL_ARRAY_BUFFER, 0, GLsizeiptr(positionCount * sizeof(float)), GL_MAP_WRITE_BIT);
-	if (positions){
-		size_t index = 0;
-		for (const auto p : *pendula){
-			index += 3;
-			for (auto x : p->X){
-				positions[index++] = float(x.x);
-				positions[index++] = float(x.y);
-				index++;
-			}
+	size_t index = 0;
+	for (const auto p : *pendula){
+		index += 3;
+		for (auto x : p->X){
+			positions[index++] = float(x.x);
+			positions[index++] = float(x.y);
+			index++;
 		}
 	}
-	simulation->pendulaMutex.unlock();
 	glUnmapBuffer(GL_ARRAY_BUFFER);
-	glBindBuffer(GL_ARRAY_BUFFER, 0);
+	simulation->pendulaMutex.unlock();
 }
 
 void GLWidget::resizeGL(int w, int h) {

src/GLWidget.h

@@ -20,7 +20,7 @@ protected:
 public slots:
 	void showMassesChanged(int state);
 private slots:
-	void initGPUMemory(const std::vector<Pendulum *> *pendula);
+	void uploadStaticDataToGPU(const std::vector<Pendulum *> *pendula);
 	void changePosition(const std::vector<Pendulum *> *pendula);
 private:
 	QOpenGLShaderProgram * program;