internal void Render(GraphicsContext gfx, float dt, IEnumerable <Entity> entities)
{
var screenSize = gfx.Screen.Surface.Size;
// Sort effect layers
EffectLayers.StableSort();
// Get first effect layer
var layer = GetEffectLayer(0);
var layerIndex = 0;
// Get initial surface
var surface = GetSurface(screenSize, layer);
// Clear initial surface with background color
gfx.Surface = surface;
gfx.Clear(BackgroundColor);
gfx.GlobalTransform *= Matrix.CreateScale(1F / layer.Downscale);
// Draw entities from back to front (negative to positive)
foreach (var entity in entities)
{
// Update Entity
entity.Update(dt);
// Entity is above layer, advance to next layer.
if (entity.Depth > layer.Depth)
{
// Apply effect to surface
gfx.Apply(layer.Effect);
// Mark surface as old surface
var oldSurface = surface;
// Get next layer and surface
layer = GetEffectLayer(++layerIndex);
surface = GetSurface(screenSize, layer);
// Copy old surface to new surface (basis)
gfx.Blit(oldSurface, surface);
// Recycle old surface (no longer needed)
SurfacePool.Recycle(oldSurface);
// Begin drawing to new layer surface
gfx.ResetState();
gfx.Surface = surface;
gfx.GlobalTransform *= Matrix.CreateScale(1F / layer.Downscale);
}
// Draw Entity
gfx.PushState();
entity.Draw(gfx, dt);
gfx.PopState();
}
// Copy surface to screen
gfx.Blit(surface, gfx.Screen.Surface);
// Recycle old surface (no longer needed)
SurfacePool.Recycle(surface);
}
