src/vs/editor/browser/viewParts/minimap/minimap.ts/Minimap/getMinimapDecorationsInViewport
class Minimap:	public getMinimapDecorationsInViewport(startLineNumber: number, endLineNumber: number): ViewModelDecoration[] {
		let visibleRange: Range;
		if (this._samplingState) {
			const modelStartLineNumber = this._samplingState.minimapLines[startLineNumber - 1];
			const modelEndLineNumber = this._samplingState.minimapLines[endLineNumber - 1];
			visibleRange = new Range(modelStartLineNumber, 1, modelEndLineNumber, this._context.viewModel.getLineMaxColumn(modelEndLineNumber));
		} else {
			visibleRange = new Range(startLineNumber, 1, endLineNumber, this._context.viewModel.getLineMaxColumn(endLineNumber));
		}
		const decorations = this._context.viewModel.getDecorationsInViewport(visibleRange);

		if (this._samplingState) {
			const result: ViewModelDecoration[] = [];
			for (const decoration of decorations) {
				if (!decoration.options.minimap) {
					continue;
				}
				const range = decoration.range;
				const minimapStartLineNumber = this._samplingState.modelLineToMinimapLine(range.startLineNumber);
				const minimapEndLineNumber = this._samplingState.modelLineToMinimapLine(range.endLineNumber);
				result.push(new ViewModelDecoration(new Range(minimapStartLineNumber, range.startColumn, minimapEndLineNumber, range.endColumn), decoration.options));
			}
			return result;
		}
		return decorations;
	}