Describe the shape of projection of vertices (vector positions of a cube) onto a 2D plane from a source...












0












$begingroup$


I am having trouble with this. I can manually calculate every single projection point onto the z=0 plane from deriving vector equations to get to the z plane for each vertices. From this I can then plot all these coordinates to find the shape. Is there a better/faster method as this question shouldn't take long.
Many thanks



The question for context is here
Here is my method










share|cite|improve this question











$endgroup$












  • $begingroup$
    The fact that this is a cube parallel to the projection plane gives it some simplifying properties. But you still have to compute some points. If you wrote out your own methods in detail for at least one point, perhaps someone would notice where you could reduce the effort.
    $endgroup$
    – David K
    Dec 13 '18 at 15:11










  • $begingroup$
    Hi David, I have updated the post with my method shown. I create vectors between the light source and each verticy and then extrapolate them to the plane z=0 to get the points of projection.
    $endgroup$
    – Adam Suttle
    Dec 13 '18 at 19:25










  • $begingroup$
    I probably should have mentioned that people here tend not to like reading the math from photographs, especially if the original is handwritten. You can look at other questions that were highly rated and got good answers to see how people format questions to get those kinds of answers. You may decide it's not worth the effort. If you want to continue, step 1 is to learn some MathJax: math.stackexchange.com/help/notation
    $endgroup$
    – David K
    Dec 13 '18 at 19:33
















0












$begingroup$


I am having trouble with this. I can manually calculate every single projection point onto the z=0 plane from deriving vector equations to get to the z plane for each vertices. From this I can then plot all these coordinates to find the shape. Is there a better/faster method as this question shouldn't take long.
Many thanks



The question for context is here
Here is my method










share|cite|improve this question











$endgroup$












  • $begingroup$
    The fact that this is a cube parallel to the projection plane gives it some simplifying properties. But you still have to compute some points. If you wrote out your own methods in detail for at least one point, perhaps someone would notice where you could reduce the effort.
    $endgroup$
    – David K
    Dec 13 '18 at 15:11










  • $begingroup$
    Hi David, I have updated the post with my method shown. I create vectors between the light source and each verticy and then extrapolate them to the plane z=0 to get the points of projection.
    $endgroup$
    – Adam Suttle
    Dec 13 '18 at 19:25










  • $begingroup$
    I probably should have mentioned that people here tend not to like reading the math from photographs, especially if the original is handwritten. You can look at other questions that were highly rated and got good answers to see how people format questions to get those kinds of answers. You may decide it's not worth the effort. If you want to continue, step 1 is to learn some MathJax: math.stackexchange.com/help/notation
    $endgroup$
    – David K
    Dec 13 '18 at 19:33














0












0








0





$begingroup$


I am having trouble with this. I can manually calculate every single projection point onto the z=0 plane from deriving vector equations to get to the z plane for each vertices. From this I can then plot all these coordinates to find the shape. Is there a better/faster method as this question shouldn't take long.
Many thanks



The question for context is here
Here is my method










share|cite|improve this question











$endgroup$




I am having trouble with this. I can manually calculate every single projection point onto the z=0 plane from deriving vector equations to get to the z plane for each vertices. From this I can then plot all these coordinates to find the shape. Is there a better/faster method as this question shouldn't take long.
Many thanks



The question for context is here
Here is my method







linear-algebra geometry vectors mathematical-physics plane-geometry






share|cite|improve this question















share|cite|improve this question













share|cite|improve this question




share|cite|improve this question








edited Dec 13 '18 at 19:23







Adam Suttle

















asked Dec 13 '18 at 13:28









Adam SuttleAdam Suttle

11




11












  • $begingroup$
    The fact that this is a cube parallel to the projection plane gives it some simplifying properties. But you still have to compute some points. If you wrote out your own methods in detail for at least one point, perhaps someone would notice where you could reduce the effort.
    $endgroup$
    – David K
    Dec 13 '18 at 15:11










  • $begingroup$
    Hi David, I have updated the post with my method shown. I create vectors between the light source and each verticy and then extrapolate them to the plane z=0 to get the points of projection.
    $endgroup$
    – Adam Suttle
    Dec 13 '18 at 19:25










  • $begingroup$
    I probably should have mentioned that people here tend not to like reading the math from photographs, especially if the original is handwritten. You can look at other questions that were highly rated and got good answers to see how people format questions to get those kinds of answers. You may decide it's not worth the effort. If you want to continue, step 1 is to learn some MathJax: math.stackexchange.com/help/notation
    $endgroup$
    – David K
    Dec 13 '18 at 19:33


















  • $begingroup$
    The fact that this is a cube parallel to the projection plane gives it some simplifying properties. But you still have to compute some points. If you wrote out your own methods in detail for at least one point, perhaps someone would notice where you could reduce the effort.
    $endgroup$
    – David K
    Dec 13 '18 at 15:11










  • $begingroup$
    Hi David, I have updated the post with my method shown. I create vectors between the light source and each verticy and then extrapolate them to the plane z=0 to get the points of projection.
    $endgroup$
    – Adam Suttle
    Dec 13 '18 at 19:25










  • $begingroup$
    I probably should have mentioned that people here tend not to like reading the math from photographs, especially if the original is handwritten. You can look at other questions that were highly rated and got good answers to see how people format questions to get those kinds of answers. You may decide it's not worth the effort. If you want to continue, step 1 is to learn some MathJax: math.stackexchange.com/help/notation
    $endgroup$
    – David K
    Dec 13 '18 at 19:33
















$begingroup$
The fact that this is a cube parallel to the projection plane gives it some simplifying properties. But you still have to compute some points. If you wrote out your own methods in detail for at least one point, perhaps someone would notice where you could reduce the effort.
$endgroup$
– David K
Dec 13 '18 at 15:11




$begingroup$
The fact that this is a cube parallel to the projection plane gives it some simplifying properties. But you still have to compute some points. If you wrote out your own methods in detail for at least one point, perhaps someone would notice where you could reduce the effort.
$endgroup$
– David K
Dec 13 '18 at 15:11












$begingroup$
Hi David, I have updated the post with my method shown. I create vectors between the light source and each verticy and then extrapolate them to the plane z=0 to get the points of projection.
$endgroup$
– Adam Suttle
Dec 13 '18 at 19:25




$begingroup$
Hi David, I have updated the post with my method shown. I create vectors between the light source and each verticy and then extrapolate them to the plane z=0 to get the points of projection.
$endgroup$
– Adam Suttle
Dec 13 '18 at 19:25












$begingroup$
I probably should have mentioned that people here tend not to like reading the math from photographs, especially if the original is handwritten. You can look at other questions that were highly rated and got good answers to see how people format questions to get those kinds of answers. You may decide it's not worth the effort. If you want to continue, step 1 is to learn some MathJax: math.stackexchange.com/help/notation
$endgroup$
– David K
Dec 13 '18 at 19:33




$begingroup$
I probably should have mentioned that people here tend not to like reading the math from photographs, especially if the original is handwritten. You can look at other questions that were highly rated and got good answers to see how people format questions to get those kinds of answers. You may decide it's not worth the effort. If you want to continue, step 1 is to learn some MathJax: math.stackexchange.com/help/notation
$endgroup$
– David K
Dec 13 '18 at 19:33










1 Answer
1






active

oldest

votes


















0












$begingroup$

You should get a hexagon a rectangle or a square.



$(frac 14, frac 54), (frac 14, frac 94),(frac 54, frac 54),(frac 54, frac 94), (-frac 12, frac 32),(-frac 12, frac 52),(frac 32, frac 52),(frac 12, frac 32)$



How do you get these.



$P_n - lambda L$ and find $lambda$ such that the $z$ component equals $0.$



enter image description here






share|cite|improve this answer











$endgroup$













  • $begingroup$
    I ended up with a pattern of imgur.com/a/XG2rsX9
    $endgroup$
    – Adam Suttle
    Dec 13 '18 at 19:37










  • $begingroup$
    That doesn't look like a cube.
    $endgroup$
    – Doug M
    Dec 13 '18 at 19:50











Your Answer





StackExchange.ifUsing("editor", function () {
return StackExchange.using("mathjaxEditing", function () {
StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
});
});
}, "mathjax-editing");

StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "69"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);

StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});

function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
noCode: true, onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});


}
});














draft saved

draft discarded


















StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3038002%2fdescribe-the-shape-of-projection-of-vertices-vector-positions-of-a-cube-onto-a%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown

























1 Answer
1






active

oldest

votes








1 Answer
1






active

oldest

votes









active

oldest

votes






active

oldest

votes









0












$begingroup$

You should get a hexagon a rectangle or a square.



$(frac 14, frac 54), (frac 14, frac 94),(frac 54, frac 54),(frac 54, frac 94), (-frac 12, frac 32),(-frac 12, frac 52),(frac 32, frac 52),(frac 12, frac 32)$



How do you get these.



$P_n - lambda L$ and find $lambda$ such that the $z$ component equals $0.$



enter image description here






share|cite|improve this answer











$endgroup$













  • $begingroup$
    I ended up with a pattern of imgur.com/a/XG2rsX9
    $endgroup$
    – Adam Suttle
    Dec 13 '18 at 19:37










  • $begingroup$
    That doesn't look like a cube.
    $endgroup$
    – Doug M
    Dec 13 '18 at 19:50
















0












$begingroup$

You should get a hexagon a rectangle or a square.



$(frac 14, frac 54), (frac 14, frac 94),(frac 54, frac 54),(frac 54, frac 94), (-frac 12, frac 32),(-frac 12, frac 52),(frac 32, frac 52),(frac 12, frac 32)$



How do you get these.



$P_n - lambda L$ and find $lambda$ such that the $z$ component equals $0.$



enter image description here






share|cite|improve this answer











$endgroup$













  • $begingroup$
    I ended up with a pattern of imgur.com/a/XG2rsX9
    $endgroup$
    – Adam Suttle
    Dec 13 '18 at 19:37










  • $begingroup$
    That doesn't look like a cube.
    $endgroup$
    – Doug M
    Dec 13 '18 at 19:50














0












0








0





$begingroup$

You should get a hexagon a rectangle or a square.



$(frac 14, frac 54), (frac 14, frac 94),(frac 54, frac 54),(frac 54, frac 94), (-frac 12, frac 32),(-frac 12, frac 52),(frac 32, frac 52),(frac 12, frac 32)$



How do you get these.



$P_n - lambda L$ and find $lambda$ such that the $z$ component equals $0.$



enter image description here






share|cite|improve this answer











$endgroup$



You should get a hexagon a rectangle or a square.



$(frac 14, frac 54), (frac 14, frac 94),(frac 54, frac 54),(frac 54, frac 94), (-frac 12, frac 32),(-frac 12, frac 52),(frac 32, frac 52),(frac 12, frac 32)$



How do you get these.



$P_n - lambda L$ and find $lambda$ such that the $z$ component equals $0.$



enter image description here







share|cite|improve this answer














share|cite|improve this answer



share|cite|improve this answer








edited Dec 13 '18 at 19:55

























answered Dec 13 '18 at 19:31









Doug MDoug M

44.8k31854




44.8k31854












  • $begingroup$
    I ended up with a pattern of imgur.com/a/XG2rsX9
    $endgroup$
    – Adam Suttle
    Dec 13 '18 at 19:37










  • $begingroup$
    That doesn't look like a cube.
    $endgroup$
    – Doug M
    Dec 13 '18 at 19:50


















  • $begingroup$
    I ended up with a pattern of imgur.com/a/XG2rsX9
    $endgroup$
    – Adam Suttle
    Dec 13 '18 at 19:37










  • $begingroup$
    That doesn't look like a cube.
    $endgroup$
    – Doug M
    Dec 13 '18 at 19:50
















$begingroup$
I ended up with a pattern of imgur.com/a/XG2rsX9
$endgroup$
– Adam Suttle
Dec 13 '18 at 19:37




$begingroup$
I ended up with a pattern of imgur.com/a/XG2rsX9
$endgroup$
– Adam Suttle
Dec 13 '18 at 19:37












$begingroup$
That doesn't look like a cube.
$endgroup$
– Doug M
Dec 13 '18 at 19:50




$begingroup$
That doesn't look like a cube.
$endgroup$
– Doug M
Dec 13 '18 at 19:50


















draft saved

draft discarded




















































Thanks for contributing an answer to Mathematics Stack Exchange!


  • Please be sure to answer the question. Provide details and share your research!

But avoid



  • Asking for help, clarification, or responding to other answers.

  • Making statements based on opinion; back them up with references or personal experience.


Use MathJax to format equations. MathJax reference.


To learn more, see our tips on writing great answers.




draft saved


draft discarded














StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3038002%2fdescribe-the-shape-of-projection-of-vertices-vector-positions-of-a-cube-onto-a%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown





















































Required, but never shown














Required, but never shown












Required, but never shown







Required, but never shown

































Required, but never shown














Required, but never shown












Required, but never shown







Required, but never shown







Popular posts from this blog

Ellipse (mathématiques)

Quarter-circle Tiles

Mont Emei