public static void SetupPaintColorMask(this SCNGeometry geometry, string name)
{
// if we've already set it up, don't do it again
if (geometry.ValueForKey(new NSString(PaintMaskColorKey)) == null)
{
if (PaintColorMaskTextures.TryGetValue(name, out string paintMask))
{
// all textures are absolute paths from the app folder
var texturePath = $"art.scnassets/textures/{paintMask}.ktx";
if (name.Contains("catapult"))
{
//os_log(.debug, "visited %s for texture", name)
}
var surfaceScript = @"
#pragma arguments
texture2d<float> paintMaskTexture;
//sampler paintMaskSampler;
float4 paintMaskColor;
#pragma body
// 0 is use diffuse texture.rgb, 1 is use paintMaskColor.rgb
float paintMaskSelector = paintMaskTexture.sample(
sampler(filter::linear), // paintMaskSampler,
_surface.diffuseTexcoord.xy).r;
_surface.diffuse.rgb = mix(_surface.diffuse.rgb, paintMaskColor.rgb, paintMaskSelector);
";
geometry.ShaderModifiers = new SCNShaderModifiers()
{
EntryPointSurface = surfaceScript
};
// mask pro
var prop = SCNMaterialProperty.Create(new NSString(texturePath));
prop.MinificationFilter = SCNFilterMode.Linear;
prop.MagnificationFilter = SCNFilterMode.Nearest;
prop.MipFilter = SCNFilterMode.Nearest;
prop.MaxAnisotropy = 1;
// set the uniforms, these will be overridden in the runtime
geometry.SetTexture("paintMaskTexture", prop);
geometry.SetFloat4(PaintMaskColorKey, SCNVector4.One);
}
}
}
// Updates the secondary image of the floor if needed
private void UpdateFloorImage(NSImage image, Slide slide)
{
// We don't want to animate if we replace the secondary image by a new one
// Otherwise we want to translate the secondary image to the new location
var disableAction = false;
if (FloorImage != image)
{
FloorImage = image;
disableAction = true;
if (image != null)
{
// Set a new material property with this image to the "floorMap" custom property of the floor
var property = SCNMaterialProperty.Create(image);
property.WrapS = SCNWrapMode.Repeat;
property.WrapT = SCNWrapMode.Repeat;
property.MipFilter = SCNFilterMode.Linear;
Floor.FirstMaterial.SetValueForKey(property, new NSString("floorMap"));
}
}
if (image != null)
{
var slidePosition = slide.GroundNode.ConvertPositionToNode(new SCNVector3(0, 0, 10), null);
if (disableAction)
{
SCNTransaction.Begin();
SCNTransaction.AnimationDuration = 0;
Floor.FirstMaterial.SetValueForKey(NSValue.FromVector(slidePosition), new NSString("floorImageNamePosition"));
SCNTransaction.Commit();
}
else
{
Floor.FirstMaterial.SetValueForKey(NSValue.FromVector(slidePosition), new NSString("floorImageNamePosition"));
}
}
}
// https://developer.apple.com/documentation/scenekit/scnshadable#1654834
// Some of these can be animated inside of an SCNTransaction.
// Sets shader modifier data onto a material or all materials in a geometry.
public static void SetTexture(this SCNGeometry geometry, string uniform, SCNMaterialProperty texture)
{
// this must be the texture name, and not the sampler name
geometry.SetValueForKey(texture, new NSString(uniform));
}
