Abstract: Roughly described, a design rule data set is developed offline from the design rules of a target fabrication process. A design rule checking method involves traversing the corners of shapes in a layout region, and for each corner, populating a layout topology database with values that depend on respective corner locations. After the layout topology database is populated, the values are compared to values in the design rule data set to detect any design rule violations. Violations can be reported in real time, while the user is manually editing the layout. Preferably corner traversal is performed using scan lines oriented perpendicularly to edge orientations, and scanning in the direction of the edge orientations. Scans stop only at corner positions and populate the layout topology database with what information can be gleaned based on the current scan line. The different scans need not reach each corner simultaneously.

Abstract: Roughly described, while manually dragging shapes during IC layout editing, editing operations determine which edges of which shapes are moving at what speed ratios. Based on the edge information and the DRC rules, the system calculates and keeps track of the minimum of the maximum distance the edges are allowed to move with the cursor without violating DRC rules, in four linear directions and all corner directions. Once a next cursor destination point is known, a DRC clean destination point is calculated based on the linear and corner bounds. If the next cursor position is beyond a the push-through distance ahead of the new DRC clean point, the editing objects are moved to the user's destination point. Otherwise, the editing objects are moved to the new DRC clean destination point, thereby stopping movement at that point.

Abstract: Roughly described, a design rule data set includes rules on derived layers. The rules are checked by traversing the corners of physical shapes, and for each corner, populating a layout topology database with values gleaned from that corner location, including values involving derived layers. After the layout topology database is populated, the values are compared to values in the design rule data set to detect any design rule violations, including violations of design rules defined on derived layers. Violations are reported in real time during manual editing of the layout. Preferably corner traversal is performed using scan lines oriented perpendicularly to edge orientations, scanning in the direction of the edge orientations. Scans stop only at corner positions on physical layers, and populate the layout topology database with what information can be gleaned based on the current scan line, including information about derived layers. The scans need not reach corners simultaneously.

Abstract: Roughly described, a design rule data set is developed offline from the design rules of a target fabrication process. A design rule checking method involves traversing the corners of shapes in a layout region, and for each corner, populating a layout topology database with values that depend on respective corner locations. After the layout topology database is populated, the values are compared to values in the design rule data set to detect any design rule violations. Violations can be reported in real time, while the user is manually editing the layout. Preferably corner traversal is performed using scan lines oriented perpendicularly to edge orientations, and scanning in the direction of the edge orientations. Scans stop only at corner positions and populate the layout topology database with what information can be gleaned based on the current scan line. The different scans need not reach each corner simultaneously.