Fix raster export scale factor (#3870)

* fix export scale factor

* export scale increment step 0.5

* fix svg to raster export on web

editor/src/messages/dialog/export_dialog/export_dialog_message_handler.rs

@@ -113,6 +113,7 @@ impl LayoutHolder for ExportDialogMessageHandler {
 				.unit("")
 				.min(0.)
 				.max((1_u64 << f64::MANTISSA_DIGITS) as f64)
+				.increment_step(0.5)
 				.disabled(self.file_type == FileType::Svg)
 				.on_update(|number_input: &NumberInput| ExportDialogMessage::ScaleFactor { factor: number_input.value.unwrap() }.into())
 				.min_width(200)

editor/src/node_graph_executor.rs

@@ -238,15 +238,19 @@ impl NodeGraphExecutor {
 			ExportBounds::Artboard(id) => document.metadata().bounding_box_document(id),
 		}
 		.ok_or_else(|| "No bounding box".to_string())?;
-		let resolution = (bounds[1] - bounds[0]).round().as_uvec2();
+
+		let resolution_in_document_space = bounds[1] - bounds[0];
+		let export_resolution = resolution_in_document_space * export_config.scale_factor;
+		let resolution = export_resolution.round().as_uvec2();
 		let transform = DAffine2::from_translation(bounds[0]).inverse();
+		let viewport = Footprint {
+			resolution,
+			transform,
+			..Default::default()
+		};
 
 		let render_config = RenderConfig {
-			viewport: Footprint {
-				resolution,
-				transform,
-				..Default::default()
-			},
+			viewport,
 			scale: export_config.scale_factor,
 			time: Default::default(),
 			pointer: DVec2::ZERO,
@@ -256,7 +260,7 @@ impl NodeGraphExecutor {
 			for_export: true,
 			for_eyedropper: false,
 		};
-		export_config.size = resolution.as_dvec2();
+		export_config.size = resolution;
 
 		// Execute the node graph
 		self.runtime_io
@@ -425,7 +429,6 @@ impl NodeGraphExecutor {
 			file_type,
 			name,
 			size,
-			scale_factor,
 			#[cfg(feature = "gpu")]
 			transparent_background,
 			artboard_name,
@@ -456,7 +459,7 @@ impl NodeGraphExecutor {
 					});
 				} else {
 					let mime = file_type.to_mime().to_string();
-					let size = (size * scale_factor).into();
+					let size = size.as_dvec2().into();
 					responses.add(FrontendMessage::TriggerExportImage { svg, name, mime, size });
 				}
 			}

editor/src/node_graph_executor/runtime.rs

@@ -1,6 +1,6 @@
 use super::*;
 use crate::messages::frontend::utility_types::{ExportBounds, FileType};
-use glam::{DAffine2, DVec2};
+use glam::{DAffine2, UVec2};
 use graph_craft::document::value::TaggedValue;
 use graph_craft::document::{NodeId, NodeNetwork};
 use graph_craft::graphene_compiler::Compiler;
@@ -84,7 +84,7 @@ pub struct ExportConfig {
 	pub scale_factor: f64,
 	pub bounds: ExportBounds,
 	pub transparent_background: bool,
-	pub size: DVec2,
+	pub size: UVec2,
 	pub artboard_name: Option<String>,
 	pub artboard_count: usize,
 }