1. A resistor string digital-to-analog converter comprising:
an input terminal receiving a digital input signal in digital code;
an output terminal revealing an analog output signal in analog voltage;
a first plurality of voltage-acquisition nodes including a first pair of nodes which is adjacent to each other;
a first plurality of resistors being connected in series via the first plurality of voltage-acquisition nodes;
a second pair of nodes revealing a pair of analog voltages;
a high-order voltage-acquisition circuit providing conduction between a respective one of the first pair of nodes and a respective one of the second pair of nodes in accordance with the digital input signal;
a low-order converter generating the analog output signal, which is obtained by interpolating one and the other of the pair of analog voltages in accordance with the digital input signal.
2. The resistor string digital-to-analog converter of claim 1, wherein the high-order voltage-acquisition circuit includes a first plurality of switches, at least some of the first plurality of switches each coupling between the respective one of the first pair of nodes and the respective one of the second pair of nodes, and
wherein a determination relating to whether each of the first plurality of switches is on or off is made based on the digital input signal.
3. The resistor string digital-to-analog converter of claim 1, wherein the low-order converter includes a second plurality of resistors being connected between one and the other of the second pair of nodes in series via a second plurality of voltage-acquisition nodes.
4. The resistor string digital-to-analog converter of claim 3, wherein the low-order converter includes a second plurality of switches, at least some of the second plurality of switches coupling between one of the second plurality of voltage-acquisition nodes and the output terminal, and
wherein a determination relating to whether each of the second plurality of switches is on or off is made based on the digital input signal.
5. A resistor string digital-to-analog converter, comprising:
an input terminal configured to receive a digitally coded digital input signal;
an output terminal configured to output an analog output voltage signal;
a plurality of voltage-acquisition nodes;
a plurality of resistors which are connected in series via the plurality of voltage-acquisition nodes;
a pair of intermediate nodes, wherein a first intermediate node of the pair of intermediate nodes is associated with a first intermediate analog voltage and a second intermediate node of the pair of intermediate nodes is associated with a second intermediate analog voltage;
a high-order voltage-acquisition circuit configured to provide conduction between the plurality of voltage-acquisition nodes and the pair of intermediate nodes based on the digital input signal; and
a low-order converter configured to generate the analog output voltage signal by interpolating the first intermediate analog voltage and the second intermediate analog voltage based on the digital input signal.
6. The resistor string digital-to-analog converter of claim 5, wherein the high-order voltage-acquisition circuit includes a first plurality of switches, each of the first plurality of switches corresponding to a respective one of the plurality of voltage-acquisition nodes, and
wherein a determination relating to whether each of the first plurality of switches is on or off is made based on the digital input signal.
7. The resistor string digital-to-analog converter of claim 6, wherein the high-order voltage-acquisition circuit further includes a second plurality of switches, a first pair of the second plurality of switches corresponding to the first intermediate node, and a second pair of the second plurality of switches corresponding to the second intermediate node, and
wherein a determination relating to whether each of the second plurality of switches is on or off is made based on the digital input signal.
8. The resistor string digital-to-analog converter of claim 7, wherein the low-order converter includes a third plurality of switches, and
wherein a determination relating to whether each of the third plurality of switches is on or off is made based on the digital input signal and the first and second intermediate analog voltages.
9. A resistor string digital-to-analog converter, comprising:
an input terminal receiving a digitally coded digital input signal;
an output terminal outputting an analog output voltage signal;
a first plurality of resistors being connected in series;
a low-order converter including a first low-order voltage input terminal and a second low-order voltage input terminal, and generating the analog output voltage signal by interpolating an analog voltage input to the first low-order voltage input terminal and an analog voltage input to the second low-order voltage input terminal based on the digital input signal; and
a high-order voltage-acquisition circuit providing conduction between one terminal of one resistor of the first plurality of resistors and the first low-order voltage input terminal, and between the other terminal of the resistor of the first plurality of resistors and the second low-order voltage input terminal based on the digital input signal;
10. The resistor string digital-to-analog converter of claim 9, wherein the high-order voltage-acquisition circuit includes a first plurality of switches, each of the first plurality of switches corresponding to a respective one of terminals of the first plurality of resistors, and
wherein a determination relating to whether each of the first plurality of switches is on or off is made based on the digital input signal.
11. The resistor string digital-to-analog converter of claim 10, wherein the high-order voltage-acquisition circuit further includes a second plurality of switches which includes a first pair of the second plurality of switches corresponding to the one terminal, and a second pair of the second plurality of switches corresponding to the other terminal, and
wherein a determination relating to whether each of the second plurality of switches is on or off is made based on the digital input signal.
12. The resistor string digital-to-analog converter of claim 11, wherein the low-order converter includes a third plurality of switches, and
wherein a determination relating to whether each of the third plurality of switches is on or off is made based on the digital input signal and the analog voltages input to the first low-order voltage input terminal and the second low-order voltage input terminal.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. Computer-implemented method for designing a three-dimensional modeled object, wherein the method comprises the steps of:
user-interacting with a screen;
defining a stroke corresponding to the user-interacting;
discretizing the stroke into a set of points;
projecting the set of points onto at least one support in a three-dimensional scene;
constructing the three-dimensional modeled object from the projected set of points and the said at least one support.
2. The method of claim 1, further comprising a step of constructing a visualization of the three-dimensional modeled object by:
computing, for each point of the projected set of points, at least two offset points, an offset point being a point positioned on said at least one support and spaced from said each point; and
computing a surface delineated by the computed at least two offset points, the surface comprising the projected set of points.
3. The method of claim 2, wherein the computing of at least two offset points comprises:
computing a poly-line linking the points of the projected set of points;
computing, for each point of the projected set of points, an offset vector {right arrow over (O)}=\u03b1*({right arrow over (n)}{right arrow over (L)}), wherein \u03b1 is a coefficient, {right arrow over (n)} is a unit vector normal to the support, {right arrow over (L)} is a vector defined by a line linking two points of the set of points forming the polyligne, {right arrow over (n)} and {right arrow over (L)} having as common origin the said each point;
determining the said at least two offset points from the offset vector {right arrow over (O)}; and
projecting the determined said at least two offset points onto said at least one support in a three-dimensional scene.
4. The method of claim 2, further comprising a step of tessellating said computed surface delineated by the computed offset.
5. The method of claim 2, wherein the step of constructing the visualization further comprises applying a shader for rendering said computed surface.
6. The method of claim 1, wherein the steps of the method are repeated with at least another one support in the three-dimensional scene.
7. A computer-implemented method for designing a three-dimensional geometrical modeled object, the method comprising the steps of:
providing a set of three-dimensional modeled objects designed by:
user-interacting with a screen;
defining a stroke corresponding to the user-interacting;
discretizing the stroke into a set of points;
projecting the set of points onto at least one support in a three-dimensional scene;
constructing the three-dimensional modeled object from the projected set of points and the said at least one support;
extracting the points of the provided set of three-dimensional modeled objects;
computing a geometrical smooth curve from the extracted points;
constructing a three-dimensional geometrical modeled object from the geometrical smooth curve.
8. The computer-implemented method of claim 7, wherein, at the step of extracting, the points are extracted according to the support on which the points are projected.
9. The computer-implemented method of claim 7, wherein the step of extracting further comprises:
user-interacting with the screen;
defining a stroke corresponding to the user-interacting;
retrieving, among the extracted points, one of three-dimensional modeled objects of the provided set of three-dimensional modeled objects and at least one support of said one of three-dimensional modeled objects retrieved;
discretizing the stroke corresponding to the user-interacting into a set of points;
projecting the points of the set of points onto the said at least one retrieved support.
10. The computer-implemented method of claim 9, wherein the step of retrieving further comprises retrieving the closest three-dimensional modeled object from a pick path starting from a cursor.
11. The computer-implemented method of claim 10, wherein the pick path comprises a ray cast from the cursor.
12. The computer-implemented method of claim 7, wherein the steps of extracting, computing and constructing are repeated for each provided three dimensional modeled objects.
13. The computer-implemented method of claim 9, wherein the steps of extracting, computing and constructing are repeated while the user interacts with the screen.
14. A computer readable storage medium having recorded thereon a computer program, for designing a three-dimensional modeled object, the computer program comprising computer code for
user-interacting with a screen;
defining a stroke corresponding to the user-interacting;
discretizing the stroke into a set of points;
projecting the set of points onto at least one support in a three-dimensional scene;
constructing the three-dimensional modeled object from the projected set of points and the said at least one support.
15. A computer readable storage medium having recorded thereon a computer program, for designing a three-dimensional geometrical modeled object, the computer program comprising computer code for:
providing a set of three-dimensional modeled objects designed by:
user-interacting with a screen;
defining a stroke corresponding to the user-interacting;
discretizing the stroke into a set of points;
projecting the set of points onto at least one support in a three-dimensional scene;
constructing the three-dimensional modeled object from the projected set of points and the said at least one support;
extracting the points of the provided set of three-dimensional modeled objects;
computing a geometrical smooth curve from the extracted points;
constructing a three-dimensional geometrical modeled object from the geometrical smooth curve.