why a Bezier curve is guaranteed to lie within the convex hull of its control points?











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why if Bernstein basis polynomials are non-negative ($ B_{k,n}(x) geq 0 $) and also due to the Partition of Unity/sum up to one ($ sum_{k=0}^n B_{k,n}(x) = 1, for all x in [0,1] $) implies Bezier curve is guaranteed to lie within the convex hull of its control points $ CH=({p_{0},p_{1},p_{2},...,p_{n}})$










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    why if Bernstein basis polynomials are non-negative ($ B_{k,n}(x) geq 0 $) and also due to the Partition of Unity/sum up to one ($ sum_{k=0}^n B_{k,n}(x) = 1, for all x in [0,1] $) implies Bezier curve is guaranteed to lie within the convex hull of its control points $ CH=({p_{0},p_{1},p_{2},...,p_{n}})$










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      favorite









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      why if Bernstein basis polynomials are non-negative ($ B_{k,n}(x) geq 0 $) and also due to the Partition of Unity/sum up to one ($ sum_{k=0}^n B_{k,n}(x) = 1, for all x in [0,1] $) implies Bezier curve is guaranteed to lie within the convex hull of its control points $ CH=({p_{0},p_{1},p_{2},...,p_{n}})$










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      why if Bernstein basis polynomials are non-negative ($ B_{k,n}(x) geq 0 $) and also due to the Partition of Unity/sum up to one ($ sum_{k=0}^n B_{k,n}(x) = 1, for all x in [0,1] $) implies Bezier curve is guaranteed to lie within the convex hull of its control points $ CH=({p_{0},p_{1},p_{2},...,p_{n}})$







      differential-geometry bezier-curve






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      edited Nov 17 at 11:34

























      asked Nov 17 at 2:13









      GreenQuestioner

      777




      777






















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          Here are the facts:




          • A convex combination of the points $p_{0},p_{1},p_{2},...,p_{n}$ is a point of the form
            $
            sum_{k=0}^n lambda_k p_k
            $
            .
            where $lambda_k ge 0$ and $sum_{k=0}^n lambda_k = 1$.


          • The convex hull of the points $p_{0},p_{1},p_{2},...,p_{n}$ is the set of all convex combination of $p_{0},p_{1},p_{2},...,p_{n}$.


          • A point on a Bézier curve is a convex combination of its control points and so is in their convex hull.







          share|cite|improve this answer





















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            Here are the facts:




            • A convex combination of the points $p_{0},p_{1},p_{2},...,p_{n}$ is a point of the form
              $
              sum_{k=0}^n lambda_k p_k
              $
              .
              where $lambda_k ge 0$ and $sum_{k=0}^n lambda_k = 1$.


            • The convex hull of the points $p_{0},p_{1},p_{2},...,p_{n}$ is the set of all convex combination of $p_{0},p_{1},p_{2},...,p_{n}$.


            • A point on a Bézier curve is a convex combination of its control points and so is in their convex hull.







            share|cite|improve this answer

























              up vote
              0
              down vote













              Here are the facts:




              • A convex combination of the points $p_{0},p_{1},p_{2},...,p_{n}$ is a point of the form
                $
                sum_{k=0}^n lambda_k p_k
                $
                .
                where $lambda_k ge 0$ and $sum_{k=0}^n lambda_k = 1$.


              • The convex hull of the points $p_{0},p_{1},p_{2},...,p_{n}$ is the set of all convex combination of $p_{0},p_{1},p_{2},...,p_{n}$.


              • A point on a Bézier curve is a convex combination of its control points and so is in their convex hull.







              share|cite|improve this answer























                up vote
                0
                down vote










                up vote
                0
                down vote









                Here are the facts:




                • A convex combination of the points $p_{0},p_{1},p_{2},...,p_{n}$ is a point of the form
                  $
                  sum_{k=0}^n lambda_k p_k
                  $
                  .
                  where $lambda_k ge 0$ and $sum_{k=0}^n lambda_k = 1$.


                • The convex hull of the points $p_{0},p_{1},p_{2},...,p_{n}$ is the set of all convex combination of $p_{0},p_{1},p_{2},...,p_{n}$.


                • A point on a Bézier curve is a convex combination of its control points and so is in their convex hull.







                share|cite|improve this answer












                Here are the facts:




                • A convex combination of the points $p_{0},p_{1},p_{2},...,p_{n}$ is a point of the form
                  $
                  sum_{k=0}^n lambda_k p_k
                  $
                  .
                  where $lambda_k ge 0$ and $sum_{k=0}^n lambda_k = 1$.


                • The convex hull of the points $p_{0},p_{1},p_{2},...,p_{n}$ is the set of all convex combination of $p_{0},p_{1},p_{2},...,p_{n}$.


                • A point on a Bézier curve is a convex combination of its control points and so is in their convex hull.








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                answered Nov 17 at 11:40









                lhf

                161k9165384




                161k9165384






























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