lumen-engine 0.2.1

use crate::node::{NodeId, NodeParams, PortRef};

use crate::gpu::{
    BoundFrame, CompiledOutput, FrameBindContext, GpuCompileNode, GpuCompiledNode, RasterHandle,
    compiler,
};

pub(crate) const SHADER: &str = include_str!("boolean.wgsl");

#[derive(Debug, Clone, Copy, PartialEq, Eq, lumen_macros::NodeEnum)]
#[repr(i64)]
pub enum BooleanOperation {
    Union = 0,
    Intersect = 1,
    Subtract = 2,
    Xor = 3,
}

impl BooleanOperation {
    pub fn from_int(value: i64) -> Self {
        match value {
            1 => Self::Intersect,
            2 => Self::Subtract,
            3 => Self::Xor,
            _ => Self::Union,
        }
    }
}

/// Combines two raster alpha masks with boolean operations.
#[derive(Debug, Clone, lumen_macros::Delegate)]
pub struct BooleanParams {
    /// Boolean operation used to combine the two input masks.
    #[meta(kind = "enum", enum_type = BooleanOperation)]
    pub operation: i64,
    /// Alpha cutoff used before evaluating the boolean operation.
    #[meta(min = 0, max = 1, step = 0.01)]
    pub threshold: f64,
}

impl Default for BooleanParams {
    fn default() -> Self {
        Self {
            operation: BooleanOperation::Union as i64,
            threshold: 0.0,
        }
    }
}

/// Combines two raster alpha masks with boolean operations.
#[derive(Debug, Clone, lumen_macros::Node)]
#[node(kind = "boolean", name = "Boolean", category = "compositing")]
pub struct Boolean {
    pub id: NodeId,
    #[params]
    pub params: BooleanParamsDelegate,

    #[input()]
    pub a: PortRef,
    #[input()]
    pub b: PortRef,
}

impl Default for Boolean {
    fn default() -> Self {
        Self {
            id: NodeId::new(0),
            params: BooleanParamsDelegate::default(),
            a: PortRef::empty(),
            b: PortRef::empty(),
        }
    }
}

#[derive(Debug, Clone)]
struct CompiledBoolean {
    node_id: NodeId,
    params: BooleanParamsDelegate,
    buffer: lumen_gpu::BufferId,
}

impl GpuCompiledNode for CompiledBoolean {
    fn node_id(&self) -> NodeId {
        self.node_id
    }

    fn bind(&self, ctx: &FrameBindContext<'_>, bound: &mut BoundFrame) -> crate::Result<()> {
        let params = self.params.eval(&crate::node::NodeParamEvalContext {
            node_id: self.node_id,
            expr: &ctx.expr_context(self.node_id, "params"),
        })?;
        let gpu_params = compiler::BooleanParams {
            values: [
                BooleanOperation::from_int(params.operation) as u32 as f32,
                params.threshold as f32,
                0.0,
                0.0,
            ],
        };
        bound.write_buffer(self.buffer, 0, bytemuck::bytes_of(&gpu_params));
        Ok(())
    }
}

impl GpuCompileNode for Boolean {
    fn compile_gpu(
        &self,
        ctx: &mut crate::gpu::CompileContext<'_>,
        port: &PortRef,
    ) -> crate::Result<CompiledOutput> {
        if port.port != "output" {
            return Err(ctx.missing_output(self.id, &port.port));
        }

        let a = ctx
            .compile_port(&self.a)?
            .into_raster(self.a.id, &self.a.port)?;
        let b = ctx
            .compile_port(&self.b)?
            .into_raster(self.b.id, &self.b.port)?;
        let size = a.domain.storage_size;
        let texture = ctx.builder_mut().texture_for(
            lumen_gpu::NodeKey(self.id.0),
            Some(format!("boolean:{}:output", self.id.0)),
            lumen_gpu::TextureDesc::storage(size, lumen_gpu::wgpu::TextureFormat::Rgba8Unorm),
        );
        let params = ctx.builder_mut().buffer_for(
            lumen_gpu::NodeKey(self.id.0),
            Some(format!("boolean:{}:params", self.id.0)),
            lumen_gpu::BufferDesc::uniform(std::mem::size_of::<compiler::BooleanParams>() as u64),
        );
        let program = ctx.builder_mut().program_for(
            lumen_gpu::NodeKey(self.id.0),
            lumen_gpu::ProgramDesc::Compute(lumen_gpu::ComputeProgramDesc {
                label: Some("boolean".to_string()),
                shader: SHADER.to_string(),
                entry: "cs_main".to_string(),
                bind_groups: lumen_gpu::BindGroupLayoutSpec::single(vec![
                    lumen_gpu::BindingLayoutEntry::texture(
                        0,
                        lumen_gpu::wgpu::ShaderStages::COMPUTE,
                    ),
                    lumen_gpu::BindingLayoutEntry::texture(
                        1,
                        lumen_gpu::wgpu::ShaderStages::COMPUTE,
                    ),
                    lumen_gpu::BindingLayoutEntry::uniform(
                        2,
                        lumen_gpu::wgpu::ShaderStages::COMPUTE,
                    ),
                    lumen_gpu::BindingLayoutEntry::storage_texture(
                        3,
                        lumen_gpu::wgpu::ShaderStages::COMPUTE,
                        lumen_gpu::wgpu::TextureFormat::Rgba8Unorm,
                        lumen_gpu::wgpu::StorageTextureAccess::WriteOnly,
                    ),
                ]),
            }),
        );
        ctx.builder_mut().compute_pass(lumen_gpu::ComputePassDesc {
            label: Some(format!("boolean:{}:apply", self.id.0)),
            owner: Some(lumen_gpu::NodeKey(self.id.0)),
            program,
            bindings: vec![
                lumen_gpu::Binding::sampled_texture(0, 0, a.texture),
                lumen_gpu::Binding::sampled_texture(0, 1, b.texture),
                lumen_gpu::Binding::uniform(0, 2, params),
                lumen_gpu::Binding::storage_texture(0, 3, texture),
            ],
            dispatch: compiler::dispatch_for(size).into(),
        });
        ctx.builder_mut().param(
            lumen_gpu::ParamKey {
                owner: lumen_gpu::NodeKey(self.id.0),
                slot: 0,
            },
            lumen_gpu::ParamTarget::Buffer(params),
        );
        ctx.register_compiled_node(CompiledBoolean {
            node_id: self.id,
            params: self.params.clone(),
            buffer: params,
        });

        Ok(CompiledOutput::Raster(RasterHandle {
            texture,
            domain: lumen_gpu::TextureDomain::full_frame(size),
            metadata: a.metadata,
        }))
    }
}