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Hi again everyone in this video. I'm going to cover the fundamentals of constructing spheres and spherical forms
在本視頻中,大家又見面了。我將介紹構建球體和球形的基礎知識
We will have a look at how to fully construct a sphere in stages
我們將看看如何分階段完整地構建一個球體
But let's have a look at what makes a sphere look like it's in perspective
不過,讓我們來看看是什麼讓球體看起來像是在透視中吧
So here you can see we have six spheres drawn from different perspective angles
在這裡,你可以看到我們從不同的角度繪製了六個球體
The silhouette of the sphere of course is just a circle
球體的輪廓當然只是一個圓形
But it's the contour lines that help communicate what perspective angle they're drawn from the contour lines are based on three intersecting ellipses and
等高線是基於三個相交的橢圓和一個相交的圓錐曲線繪製的。
You can see here me tracing off those ellipses. There's the first one there's the second one and
你可以看到我在描畫這些省略號。這是第一個,這是第二個,還有
Here's the third one
這是第三張
And those ellipses are based on the intersection of three planes
這些橢圓基於三個平面的交點
So let's simplify this and just take a look at one sphere from one particular angle in order to
是以,讓我們簡化一下,只從一個特定的角度觀察一個球體,以便
Understand how to construct these things. So here I have two spheres and these spheres are sitting on a horizontal surface
瞭解如何構造這些東西。這裡我有兩個球體,這些球體位於一個水準面上
How do we know that they're sitting on a horizontal surface?
我們怎麼知道它們是坐在水準面上呢?
Well, if we have a look at our ellipse lying horizontally
那麼,如果我們看看水準放置的橢圓
Remember from our rule
記住我們的規則
The major axis is horizontal to our view that ellipse would be sitting in a square
在我們看來,主軸是水準的,橢圓將位於正方形中
That is horizontal and our minor axis is straight up and down vertical
這是水準軸,我們的小軸是直上直下的垂直軸
This particular drawing is showing that we are slightly above the sphere
這幅圖顯示我們略高於球面
Because of how open that minor axis is
因為小軸是開放的
This sphere here is
這裡的球體是
Drawn closer to our eye level and what's the rule?
拉近到我們的視線水準,規則是什麼?
Well, the flatter the minor axis is the closer it is to the horizon line
那麼,小軸越扁平,就越接近地平線
So we're still using the same principles that we've learned about sketching ellipses in perspective
是以,我們仍然採用我們已經學到的透視橢圓素描的原則
So let's take the perspective angle of this sphere and I'm going to use it to show you how to fully construct
是以,讓我們從這個球體的透視角度出發,我將用它來向大家展示如何完整地構建
This sphere in stages using three intersecting planes
這個球體分階段使用三個相交平面
So here we have the redrawn sphere using color-coordinated contour lines
是以,我們在這裡使用顏色協調的輪廓線重新繪製了球體
To the right. This is the full construction of that sphere. You can see here. I've drawn a very light estimated perspective cube and
在右邊。這是球體的完整結構。你可以看到這裡。我畫了一個估計值很低的透視立方體,然後
It's important to have your proportions correct particularly of the square planes
正確的比例很重要,尤其是正方形平面的比例
That we know that the ellipses are going to sit inside
我們知道橢圓將位於內部
The more accurate your ellipses are going to be the more accurate the contour lines to indicate surface are going to be
橢圓越精確,表示表面的等高線就越精確
Now I've left out the major and minor axes from this sketch just to keep it cleaner but take note of the major axis of this red ellipse and
現在,為了使草圖更簡潔,我省略了主軸和次軸,但請注意這個紅色橢圓的主軸和次軸。
The minor axis is actually a line going to the left vanishing point on this green ellipse the major axis
小軸實際上是一條通向綠色橢圓左側消失點的直線。
Is 90 degrees to the minor axis and that minor axis is going to the right vanishing point
與小軸成 90 度,小軸指向右側的消失點
Of course our blue ellipse, which is a horizontal ellipse its minor axis is vertical and major axis is horizontal and 90 degrees to that minor axis and
當然,我們的藍色橢圓是一個水準橢圓,它的小軸是垂直的,主軸是水準的,與小軸成 90 度,而主軸與小軸成 90 度。
Just to clarify that here. I'm just showing the three
在此澄清一下。我只是展示了三個
Ellipses on their individual planes, and I've indicated the major and minor axis of each of those ellipses
橢圓在各自的平面上,我標出了每個橢圓的主軸和次軸
You can see that on the right
從右邊可以看到
Vertical ellipse, which is this green one the minor axis would be going to the vanishing point to the right
垂直橢圓,也就是這個綠色的橢圓,小軸將指向右側的消失點
And on the left vertical plane, which is this red ellipse its minor axis would be going to the left
而在左邊的垂直面上,也就是這個紅色的橢圓,它的小軸會向左移動
Vanishing point and of course the horizontal ellipse, which is this blue one. We have the centerline which is vertical
消失點,當然還有水準橢圓,也就是這個藍色的橢圓。我們有垂直的中心線
That's your minor axis 90 degrees to that would be your major axis the view up here is the same construction, but without the full construction of the cube and
這裡的視圖是相同的結構,但沒有立方體的完整結構和
You can see that we've got the three intersecting planes and the ellipses that sit on those planes
你可以看到,我們有三個相交的平面和位於這些平面上的橢圓
We're going to use this view to help us construct
我們將使用該視圖來幫助我們構建
Radiused corners, so let's have a closer look at that
弧形邊角,讓我們來仔細看看吧
Firstly let's have a look at a cube that has radiused corners, and you can see this cube here
首先,讓我們來看看一個四角呈弧形的立方體。
Which started off with sharp edges and sharp corners has actually been rounded off with radiused corners
從最初的銳邊尖角,到現在的圓角弧面
Each of these images here are actually part of the construction of a sphere
這裡的每張圖片實際上都是球體結構的一部分
So this bottom corner here bottom left corner
是以,左下角的這個底角
Top left corner front corner
左上角 前角
Top right corner and bottom right corner
右上角和右下角
This sketch doesn't show the construction of the far side top corner, but in fact if we joined all of these corners
這張草圖沒有顯示遠側頂角的構造,但事實上,如果我們將所有這些角連接起來
Together we would actually make up a sphere
我們實際上組成了一個球體
The outer images shown here are basically each of these corners without the full construction
這裡顯示的外層圖片基本上是每一個沒有完整結構的角
So in heavier line weight that would be the object as a solid or the corner as a solid and of course light line work to show the internal construction of that edge
是以,在較重的線條重量中,物體是實心的,角落是實心的,當然還有輕線條,以顯示邊緣的內部結構。
That would be the front
這將是前面
Corner, and of course the far side right corner and again the bottom left corner
角,當然還有最邊上的右角和左下角
The bottom leading corner and the bottom right corner drawn without all of its construction
繪製的左下角和右下角不包括所有結構
So let's see how to construct each of these corners by using our early image showing the intersecting planes and ellipses
那麼,讓我們看看如何利用早期顯示相交平面和橢圓的影像來構造這些角吧
Okay, so here you can see I've digitally replicated the construction of a sphere
好了,在這裡你可以看到我用數字技術複製了一個球體的結構
Using the construction with the three planes and the ellipses and from this I'll show you how to construct
利用三個平面和橢圓的構造,我將向你展示如何構造
The radius corners on the top surface of this sphere
球體頂面的半徑角
You can see there are four quarters or four quadrants on the top surface above that horizontal plane and each of those
你可以看到,在水平面上方的頂面上有四個刻度或四個象限,每個刻度或象限都是
Corners are actually little cubes and we can take the top left corner to construct this radius corner
角實際上是一個小方塊,我們可以取左上角來構造這個半徑角
Basically, I'm just going to define
基本上,我只是要定義
The surface that we would see
我們將看到的表面
There's the leading radius that part of the ellipse will also have that part of the horizontal ellipse
橢圓的前導半徑也是水準橢圓的前導半徑。
This part of the green ellipse on the right vertical side and
右側垂直方向上的綠色橢圓部分和
The radius of the circle to construct the far side radius corner we would take the far side cube
圓的半徑來構造遠側半徑角,我們將取遠側立方體
Define the leading edge
確定前緣
Define the base edge or the baseline edge
定義基準邊或基線邊
Trace off the sections of the ellipses on the left vertical face
在左側垂直面上描出橢圓的部分
On the right vertical face
在右側垂直面上
And of course
當然還有
The circle
圓圈
Here we have the top right radius corner and it's basically the flip side of the top left radius corner
這裡是右上角半徑角,基本上是左上角半徑角的翻轉面
Again we trace off the vertical edge horizontal edge that part of the right vertical ellipse
同樣,我們從垂直邊緣的水準邊緣描出右側垂直橢圓的部分
This part of the left vertical ellipse it will tangent the radius of the circle
左側垂直橢圓的這一部分將與圓的半徑相切
Part of the horizontal ellipse and of course that should tangent smoothly to the perimeter of the circle itself or the sphere itself
水準橢圓的一部分,當然應該與圓本身或球體本身的周長平滑相切
And the last of the four radius corners on this top surface would be the forward facing radiused corner and you can see
頂面四個弧形角中的最後一個是朝前的弧形角,你可以看到
We're taking this section of the horizontal ellipse that section of the left
我們將水準橢圓的這一部分,即左側的那一部分
Vertical side ellipse and this section of the right
垂直側橢圓和右側的這一部分
Vertical side ellipse and that's it. If I wanted to show the inside construction of each of these radius corners, of course, you can come in with lighter line weight and define these construction lines
垂直側橢圓,就是這樣。當然,如果我想顯示每個半徑角的內部結構,可以使用較輕的線條重量來定義這些結構線
So that's if we want to show all the internal construction
是以,如果我們想展示所有的內部結構
I'm using a finer point fineliner to do this and
我是用較細的細線筆畫的,而且
Obviously these aren't shown on the images on the top row here
很明顯,這裡最上面一排的圖片上沒有顯示這些內容
Okay, so let's now have a look at constructing the radius corners on the bottom surface of this sphere
好了,現在讓我們看看如何在球體底面上構建半徑角
Again, we'll still have four quadrants
同樣,我們仍然有四個象限
Four little cubes and we trace off the edges and parts of the radius of these ellipses to construct our corner
四個小方塊,我們沿著這些橢圓的邊緣和部分半徑來構建我們的角
So with the bottom left radius corner, I'm tracing off
是以,在左下角的半徑角上,我將描畫出
That horizontal and vertical line it gives me a sharp edge and corner
這條橫線和豎線給我帶來了鮮明的稜角
Then of course, I'm going to trace off this section of the horizontal
當然,我還要把這部分水平線描畫出來。
Ellipse this part of the left vertical ellipse and here's the tangent which would be the outline or the perimeter of the circle
將左側垂直橢圓的這一部分橢圓化,這裡是切線,也就是圓的輪廓或周長
The far side lower radius corner which would be the box at the back of this lower surface we would see a leading corner
遠側的下半圓角,也就是下表面背面的方框,我們會看到一個引角
Then I would have this section of the yellow ellipse, which is that left vertical ellipse this section of the right vertical ellipse
然後,我將把這部分黃色橢圓,也就是左邊的垂直橢圓 這部分右邊的垂直橢圓
And of course that section of the horizontal ellipse
當然,水準橢圓的那一部分
Moving along to the right side lower radius corner
移至右側下半徑角
I'm tracing off again an edge that I can see
我再次描畫出我能看到的邊緣
Oops a little bit wonky and then I would see that this section of the top
哎呀,有點亂,然後我會看到頂部的這一部分
Ellipse
橢圓形
This section of the right
右側的這一部分
Vertical ellipse, which is the green one and of course the perimeter of the actual sphere itself and
垂直橢圓,也就是綠色的那個,當然還有實際球體本身的周長,以及
To finish off. Here's the near side lower radius corner
最後。這是近側下半徑角
Again we'll see the top edge of that surface
我們將再次看到該表面的頂部邊緣
This would be the leading edge which is this section of the horizontal ellipse the blue one
這將是前緣,也就是水準橢圓的藍色部分
This is a compound curve here, so it's this section of the right vertical ellipse the orange ellipse this section of the left vertical ellipse, which is the green one and of course, we're going to finish off with the perimeter or the limit of the sphere
這是一條複合曲線,是以它是右側垂直橢圓的這一部分,即橙色橢圓 左側垂直橢圓的這一部分,即綠色橢圓,當然,最後我們還要計算球體的周長或極限。
Which would tangent all of that
這將使所有這些問題變得更加複雜
Again, these corners are drawn as solid objects, but if I wanted to include the internal construction
同樣,這些角也是作為實體對象繪製的,但如果我想將內部結構包括在內
Just going back to these original trace offs. I would see this
只是回到這些原始的痕跡。我會看到這個
Inside edge
內側邊緣
I wouldn't see anything more than that for that far side radius corner
我認為最邊上的半徑角不會超過這個範圍
I would see or include this edge
我會看到或包括這條邊
Which is the far side edge of that ellipse?
哪個是橢圓的遠邊?
and here I would see a combination of the far side vertical line and
在這裡,我會看到遠側垂直線與
This part of the left or orange ellipse and this part of the right
左側或橙色橢圓的這一部分和右側的這一部分
Vertical or green ellipse, so that would be the construction line
垂直或綠色橢圓,是以這將是施工線
Internal wireframe of each of those corners
每個角的內部線框
Okay, so other than radius corners
好吧,除了半徑角
I wanted to show you that we can build sphere based forms by still using the same construction and
我想向大家展示的是,我們仍然可以使用相同的結構和方法來創建基於球形的表單。
You can see quite a few of them on this page
您可以在本頁看到其中的許多內容
You can see I've done the same as previously in that
你可以看到,我的操作與之前的一樣,即
I'm just using heavier line weight to define the form that I want based on the construction of a sphere and above the full construction is the actual object itself and
我只是在球體結構的基礎上使用更重的線條來定義我想要的形式,而在完整結構的上方就是實際物體本身,並且
I've chosen to include the contour lines and center lines and you can see how by including those it clearly defines the shape of the actual surface of this
我選擇了包括輪廓線和中心線,你可以看到通過包括這些線,如何清晰地定義了這個實際表面的形狀。
Hemisphere so similar to drawing boxes and cylinders and cones in isolation until
半球與單獨繪製方框、圓柱和圓錐如此相似,直到
You get used to drawing them accurately and in perspective
你會習慣於準確、透視地繪製它們
I'd strongly suggest drawing spheres and spherical type forms in isolation just like this
我強烈建議單獨繪製球體和球形,就像這樣
Then later on you can apply what you've learned from drawing these things and adding them to your complex
然後,你就可以運用你從畫這些東西中學到的知識,將它們添加到你的綜合作品中去。
Geoform constructions and I'd like to see you attempt that and include some of these features in those sketches
我希望看到你嘗試這樣做,並在草圖中加入一些這樣的特徵
When you add these forms to your complex structures, just think about the fact that
當您在複雜結構中添加這些表單時,請考慮以下事實
Each of these ellipses sit inside squares
每個橢圓都位於正方形內
So if you can map a square on the surface of your structure, you can actually construct the ellipse. For example this hemisphere
是以,如果能在結構表面繪製出一個正方形,就能真正構建出橢圓。例如這個半球形
We know that the ellipse is
我們知道橢圓是
Horizontal
橫向
That ellipse sits inside a square and if you can map that square on the surface of your complex structure
該橢圓位於一個正方形內,如果能將該正方形映射到複雜結構的表面上
You can start to build this hemisphere
您可以開始構建這個半球形
If you wanted to do a half a sphere on the side of a vertical wall
如果你想在垂直牆壁的一側做一個半球體
If you can map that square in perspective on your vertical wall
如果您能在垂直牆面上繪製正方形透視圖
You can map that ellipse and then you can map the rest of this structure so that you can build all the construction
您可以繪製該橢圓,然後繪製該結構的其餘部分,這樣您就可以建造所有建築
So what we've covered in this video is essentially fundamentals of spherical and spherical form construction
本視頻主要介紹了球形和球形結構的基本原理
Remember, these are fundamentals and as long as we understand those fundamentals
請記住,這些都是基本要素,只要我們理解了這些基本要素
We can apply those to the construction of freehand sketches
我們可以將其應用於自由素描的創作中
And that way we can draw these types of features with some accuracy
這樣,我們就能準確地繪製出這些類型的特徵了