Numbers not adding up? (What am I not understanding here?) [closed]
- by Milo
I have the following output:
Short version:
The last numbers on the S= lines increase by H and SHOULD theoretically be linearly decreasing, ex: -285,-290,-295...but the fourth one jumps to -252. Yet, every other number is linearly increasing. Why is that and how could I fix that?
To explain the numbers, it comes from slider value changed. I have a slider whose value is used to generate the float on the next line. Everything should be growing linearly here.
This value is used to determine the size of a flow layout and it is also used in conjunction with a scrollbar. But basically I have a background for the flow layout and that number is the start location for rendering it. The numbers should linearly change to create a smooth transition but when that one jumps, it looks weird on screen and I dont understand why the numbers are jumping every X slider value changes. Mathematically what could be causing this?
Here is the code for rendering the background and the function that is called when value changes:
void LobbyTableManager::renderBG( GraphicsContext* g, agui::Rectangle& absRect, agui::Rectangle& childRect )
{
float scale = 0.35f;
int w = m_bgSprite->getWidth() * getTableScale() * scale;
int h = m_bgSprite->getHeight() * getTableScale() * scale;
int numX = ceil(absRect.getWidth() / (float)w) + 2;
int numY = ceil(absRect.getHeight() / (float)h) + 2;
int startY = childRect.getY();
int numAttempts = 0;
while(startY + h < absRect.getY() && numAttempts < 1000)
{
startY += h;
if(moo)
{
std::cout << startY << ",";
}
numAttempts++;
}
g->holdDrawing();
for(int i = 0; i < numX; ++i)
{
for(int j = 0; j < numY; ++j)
{
g->drawScaledSprite(m_bgSprite,0,0,m_bgSprite->getWidth(),m_bgSprite->getHeight(),
absRect.getX() + (i * w) + (offsetX),absRect.getY() + (j * h) + startY,w,h,0);
}
}
g->unholdDrawing();
g->setClippingRect(cx,cy,cw,ch);
}
void LobbyTableManager::setTableScale( float scale )
{
scale += 0.3f;
scale *= 2.0f;
float scrollRel = m_vScroll->getRelativeValue();
setScale(scale);
rescaleTables();
resizeFlow();
updateScrollBars();
float newVal = scrollRel * m_vScroll->getMaxValue();
m_vScroll->setValue(newVal);
}
void LobbyTableManager::valueChanged( agui::VScrollBar* source,int val )
{
m_flow->setLocation(0,-val);
}
Any insight on mathematically why the anomaly might happen every Nth time would be helpful.
I just dont understand why if every number linearly increates it jumps from -295 to -252!
Thanks
