CARTO: Fix seams between tiles in RasterTileLayer

modules/carto/src/layers/post-process-utils.ts

@@ -3,7 +3,9 @@
 // Copyright (c) vis.gl contributors
 
 import {Framebuffer, TextureProps} from '@luma.gl/core';
+import type {ShaderPass} from '@luma.gl/shadertools';
 import {
+  _ConstructorOf,
   CompositeLayer,
   Layer,
   LayerContext,
@@ -63,8 +65,10 @@ class DrawCallbackLayer extends Layer {
  * Resulting layer must be used as a sublayer of a layer created
  * with `PostProcessModifier`
  */
-export function RTTModifier(BaseLayer) {
+export function RTTModifier<T extends _ConstructorOf<Layer>>(BaseLayer: T): T {
+  // @ts-expect-error initializeState is abstract
   return class RTTLayer extends BaseLayer {
+    // @ts-expect-error typescript doesn't see static property
     static layerName = `RTT-${BaseLayer.layerName}`;
 
     draw(this: RTTLayer, opts: any) {
@@ -181,5 +185,30 @@ export function PostProcessModifier<T extends Constructor<DrawableCompositeLayer
 
       this.internalState.renderInProgress = false;
     }
+
+    _finalize(): void {
+      this.internalState.renderBuffers.forEach((fbo: Framebuffer) => {
+        fbo.destroy();
+      });
+      this.internalState.renderBuffers = null;
+      this.internalState.postProcess.cleanup();
+    }
   };
 }
+
+const fs = /* glsl */ `\
+vec4 copy_filterColor_ext(vec4 color, vec2 texSize, vec2 texCoord) {
+  return color;
+}
+`;
+
+/**
+ * Copy
+ * Simple module that just copies input color to output
+ */
+export const copy = {
+  name: 'copy',
+  fs,
+  getUniforms: () => ({}),
+  passes: [{filter: true}]
+} as const satisfies ShaderPass<{}>;

modules/carto/src/layers/raster-layer-vertex.glsl.ts

@@ -23,12 +23,14 @@ out vec4 position_commonspace;
 
 void main(void) {
   // Rather than positioning using attribute, layout pixel grid using gl_InstanceID
-  vec2 common_position = column.offset.xy;
+  vec2 tileOrigin = column.offset.xy;
   float scale = column.widthScale; // Re-use widthScale prop to pass cell scale
 
   int yIndex = - (gl_InstanceID / BLOCK_WIDTH);
   int xIndex = gl_InstanceID + (yIndex * BLOCK_WIDTH);
-  common_position += scale * vec2(float(xIndex), float(yIndex - 1));
+
+  // Avoid precision issues by applying 0.5 offset here, rather than when laying out vertices
+  vec2 cellCenter = scale * vec2(float(xIndex) + 0.5, float(yIndex) - 0.5);
 
   vec4 color = column.isStroke ? instanceLineColors : instanceFillColors;
 
@@ -39,7 +41,7 @@ void main(void) {
   // Get position directly from quadbin, rather than projecting
   // Important to set geometry.position before using project_ methods below
   // as geometry.worldPosition is not set (we don't know our lat/long)
-  geometry.position = vec4(common_position, 0.0, 1.0);
+  geometry.position = vec4(tileOrigin + cellCenter, 0.0, 1.0);
   if (project.projectionMode == PROJECTION_MODE_WEB_MERCATOR_AUTO_OFFSET) {
     geometry.position.xyz -= project.commonOrigin;
   }
@@ -63,12 +65,12 @@ void main(void) {
 
   geometry.pickingColor = instancePickingColors;
 
-  // project center of column
-  vec2 offset = (vec2(0.5) + positions.xy * strokeOffsetRatio) * cellWidth * shouldRender;
-  vec3 pos = vec3(offset, project_size(elevation));
-  DECKGL_FILTER_SIZE(pos, geometry);
+  // Cell coordinates centered on origin
+  vec2 base = positions.xy * scale * strokeOffsetRatio * column.coverage * shouldRender;
+  vec3 cell = vec3(base, project_size(elevation));
+  DECKGL_FILTER_SIZE(cell, geometry);
 
-  geometry.position.xyz += pos;
+  geometry.position.xyz += cell;
   gl_Position = project_common_position_to_clipspace(geometry.position);
 
   geometry.normal = project_normal(normals);

modules/carto/src/layers/raster-layer.ts

@@ -16,6 +16,7 @@ import {quadbinToOffset} from './quadbin-utils';
 import {Raster} from './schema/carto-raster-tile-loader';
 import vs from './raster-layer-vertex.glsl';
 import {createBinaryProxy} from '../utils';
+import {RTTModifier} from './post-process-utils';
 
 const defaultProps: DefaultProps<RasterLayerProps> = {
   ...ColumnLayer.defaultProps,
@@ -30,7 +31,8 @@ const defaultProps: DefaultProps<RasterLayerProps> = {
 };
 
 // Modified ColumnLayer with custom vertex shader
-class RasterColumnLayer extends ColumnLayer {
+// Use RTT to avoid inter-tile seams
+class RasterColumnLayer extends RTTModifier(ColumnLayer) {
   static layerName = 'RasterColumnLayer';
 
   getShaders() {
@@ -143,7 +145,18 @@ export default class RasterLayer<DataT = any, ExtraProps = {}> extends Composite
         offset,
         lineWidthScale, // Re-use widthScale prop to pass cell scale,
         highlightedObjectIndex,
-        highlightColor
+        highlightColor,
+
+        // RTT requires blending otherwise opacity < 1 blends with black
+        // render target
+        parameters: {
+          blendColorSrcFactor: 'one',
+          blendAlphaSrcFactor: 'one',
+          blendColorDstFactor: 'zero',
+          blendAlphaDstFactor: 'zero',
+          blendColorOperation: 'add',
+          blendAlphaOperation: 'add'
+        }
       }
     );
   }

modules/carto/src/layers/raster-tile-layer.ts

@@ -2,13 +2,21 @@
 // SPDX-License-Identifier: MIT
 // Copyright (c) vis.gl contributors
 
-import {CompositeLayer, CompositeLayerProps, DefaultProps, Layer, LayersList} from '@deck.gl/core';
+import {
+  CompositeLayer,
+  CompositeLayerProps,
+  DefaultProps,
+  FilterContext,
+  Layer,
+  LayersList
+} from '@deck.gl/core';
 import RasterLayer, {RasterLayerProps} from './raster-layer';
 import QuadbinTileset2D from './quadbin-tileset-2d';
 import type {TilejsonResult} from '@carto/api-client';
 import {injectAccessToken, TilejsonPropType} from './utils';
 import {DEFAULT_TILE_SIZE} from '../constants';
 import {TileLayer, TileLayerProps} from '@deck.gl/geo-layers';
+import {copy, PostProcessModifier} from './post-process-utils';
 
 export const renderSubLayers = props => {
   const tileIndex = props.tile?.index?.q;
@@ -18,6 +26,7 @@ export const renderSubLayers = props => {
 
 const defaultProps: DefaultProps<RasterTileLayerProps> = {
   data: TilejsonPropType,
+  refinementStrategy: 'no-overlap',
   tileSize: DEFAULT_TILE_SIZE
 };
 
@@ -31,6 +40,16 @@ type _RasterTileLayerProps<DataT> = Omit<RasterLayerProps<DataT>, 'data'> &
     data: null | TilejsonResult | Promise<TilejsonResult>;
   };
 
+class PostProcessTileLayer extends PostProcessModifier(TileLayer, copy) {
+  filterSubLayer(context: FilterContext) {
+    // Handle DrawCallbackLayer
+    const {tile} = (context.layer as Layer<{tile: any}>).props;
+    if (!tile) return true;
+
+    return super.filterSubLayer(context);
+  }
+}
+
 export default class RasterTileLayer<
   DataT = any,
   ExtraProps extends {} = {}
@@ -50,7 +69,7 @@ export default class RasterTileLayer<
     if (!tileJSON) return null;
 
     const {tiles: data, minzoom: minZoom, maxzoom: maxZoom} = tileJSON;
-    const SubLayerClass = this.getSubLayerClass('tile', TileLayer);
+    const SubLayerClass = this.getSubLayerClass('tile', PostProcessTileLayer);
     return new SubLayerClass(this.props, {
       id: `raster-tile-layer-${this.props.id}`,
       data,