為科幻航天器創(chuàng)建紋理

在我的教程系列的第二部分中，我將向您展示我通常在我的項目中使用的紋理過程。 我將逐步展示如何覆蓋創(chuàng)建模型紋理的不同階段，首先建立顏色，然后添加損傷和風(fēng)化，最后添加一些污垢。

我還將分享我在Photoshop中使用的手繪技術(shù)，以及如何使用紋理貼圖獲得某些效果。 我還將介紹如何使用物質(zhì)設(shè)計師中的金屬耐候過濾器來制造灰塵的基本解釋。

我使用PBR系統(tǒng)的Metalness / Roughness工作流來處理這個過程。 我將解釋PBR的基本原則，但如果您想閱讀完整的理論，您可以從Allegorithmic下載免費的綜合PBR指南。

In this second part of my tutorial series, I will show you the texturing process I usually use in my projects. I will show step by step how I cover the different stages in creating the textures of a model, starting by establishing the colors, followed by adding damage and weathering, and finally adding some dirtiness.

I will also share the hand-painting techniques I use in Photoshop, as well as how to obtain certain effects using texture maps. I will also cover a very basic explanation of how to use the Metal Weathering filter in Substance Designer to make dust.

I approach this process using the PBR system's Metalness/Roughness workflow. I am going to explain the very basic principles of PBR, but if you want to read the full theory, you can download the free Comprehensive PBR Guide from Allegorithmic.

I hope you find my techniques and methods useful to use in your own projects.

Step 01: Making UVs

To make the UVs I use UVLayout. I've been using it for about six years now, as it gives me the necessary tools to makes UVs easy and quick. Feel free to use the software of your choice to make the UVs - the important thing to take into account in this process is to hide the seams as much as possible. Try to make cuts between panels and inside grooves. Try not to make them in the middle of a visible area unless you don't have any other choice; in that case, you will need to work that area in detail in the texture to cover up the seam as much as possible.

步驟01：制作UV

為了使UVs使用UVLayout。 我已經(jīng)使用了大約六年了，因為它給了我必要的工具，使紫外線容易和快速。 隨意使用您選擇的軟件來制造UV-在此過程中要考慮的重要事項是盡可能地隱藏接縫。 嘗試在面板和內(nèi)部凹槽之間切割。 盡量不要讓它們在可見區(qū)域的中間，除非你沒有其他選擇; 在這種情況下，您將需要在紋理中詳細地處理該區(qū)域以盡可能地覆蓋接縫。

Step 02: Using checker maps

Another important thing to take into account when packing the UVs is to keep all the islands totally vertical or horizontal, because it will make the texturing process easier when painting or using tile maps of panels and straight lines. Always avoid any oblique islands. You can check by using a checkered map on the object.

步驟02：使用檢查圖

包裝紫外線時要考慮的另一個重要事情是保持所有的島嶼完全垂直或水平，因為當(dāng)繪畫或使用面板和直線的瓷磚地圖時，會使紋理過程更容易。 始終避免任何傾斜的島嶼。 您可以使用對象上的方格圖進行檢查。

Step 03: Texture sheets

Feel free to make two or three texture sheets for the ship. You can divide it as you want, for example, one texture sheet for the front section and one for the rear section. For the purposes of this tutorial and to keep things easy, I keep the whole ship in a single 4096 x 4096 texture sheet and the cables in one 1024 x 1024 texture sheet.

步驟03：紋理紙

隨意為船舶制作兩三張紋理紙。 您可以根據(jù)需要進行劃分，例如，前面部分的一張紋理表，后部的一張紋理表。 為了本教程的目的，為了簡便起見，我將整個船只保存在一個單獨的4096 x 4096紋理表和一個1024 x 1024紋理表中的電纜。

Step 04: Rendering out the maps

Before starting to paint the textures, I render out all the maps I'm going to need. The first one is a template for the UVs, which I'll use in Screen blending mode in Photoshop as a reference for the different objects' placement.

Inside 3ds Max, apply an 'Unwrap UVW' modifier to the object and open the UV editor, then under Tools > Render UV Template, a new window will appear with the options for your render. Just put the correct size of the map and click Render.

The second one I always make is a mask map, which I use in Photoshop's alpha channel to make quick and easy selections of the areas I need. I've got this map in the same window as the UV template, but this time I change some parameters to get the black-and-white image and save it as a TGA file.

Finally for the ambient occlusion (AO) map I use Faogen, a software that make AO maps very quickly and accurately. Feel free to use the software of your choice to make AO maps - the important thing is to have the occlusions very visible in the map.

步驟04：渲染地圖

在開始繪制紋理之前，我渲染出我需要的所有地圖。第一個是UVs的模板，我將在Photoshop中使用屏幕混合模式作為不同對象的位置的參考。

在3ds Max內(nèi)部，將“打開UVW”修飾符應(yīng)用于對象并打開UV編輯器，然后在“工具”>“渲染UV模板”下，將出現(xiàn)一個新窗口，其中包含您的渲染選項。只需放置正確的地圖大小，然后單擊“渲染”。

我總是做的第二個是一個掩模圖，我在Photoshop的Alpha通道中使用，以便快速，輕松地選擇我需要的區(qū)域。我在UV模板的同一個窗口中有這個地圖，但是這次我改變了一些參數(shù)來獲取黑白圖像并將其保存為TGA文件。

最后，對于環(huán)境遮擋（AO）地圖，我使用Faogen，這是一種使AO映射非�？焖贉�(zhǔn)確的軟件。隨意使用您選擇的軟件制作AO地圖 - 重要的是讓地圖中的遮擋非常明顯。

Step 05: BPR Metalness/Roughness workflow

For this project I'm using PBR rendering with a Metalness/Roughness Workflow. I need three maps for this:

1. Albedo map, where the colors represent the albedo for non-metallic materials and reflectance values for metals.

2. Metallic map, where white represents metal and the black represents non-metal.

3. Roughness map, where white represents rough surfaces and black represents smooth surfaces.

To learn more about the characteristics of each of the maps and take a deeper look at the PBR workflow, you can look at the Comprehensive PBR Guide by Allegorithmic.

Keeping that knowledge in mind, I start to build all the maps simultaneously in Photoshop, adding details, damage, dirt, and so on, step by step in different layers while constantly checking the process in Marmoset Toolbag 2.

步驟05：BPR金屬/粗糙度工作流程

對于這個項目，我正在使用具有金屬/粗糙度工作流程的PBR渲染。 我需要三張地圖：

1.反照率圖，其中顏色代表非金屬材料的反照率和金屬的反射率值。

金屬圖，白色代表金屬，黑色代表非金屬。

粗糙度圖，白色表示粗糙表面，黑色表示光滑表面。

要了解有關(guān)每個地圖特征的更多信息，并對PBR工作流程進行更深入的了解，可以參考Allegorithmic的綜合策略路由指南。

牢記這些知識，我開始在Photoshop中同時構(gòu)建所有的地圖，添加細節(jié)，損壞，污垢等等，一步一步地在不同的層次中，同時不斷檢查Marmoset Toolbag 2中的過程。

Step 06: Establish the different colors

To start the texturing process, I first establish all the colors of the ship. I create a base layer of solid color that is the base color of the ship (in this case, blue). On top of this one, I start to create more solid color layers with all the different colors, and mask the desired pieces of the ship (I use the mask map I previously made in 3ds Max to help me select the areas and mask them). I basically make variations of blue, some black pieces and some different tones of gray.

The colors in this case represent the paint on the metal, so the roughness map should be the same in all the colors, even though I prefer to add some variation to break the homogeneity.

The metal map is all black for now since I haven't established any raw metal yet.

步驟06：建立不同的顏色

要開始紋理化處理，我首先建立船的所有顏色。 我創(chuàng)建一個基色的基色，這是基本顏色的船（在這種情況下，藍色）。 在此之上，我開始創(chuàng)建更加純凈的顏色層與所有不同的顏色，并掩蓋所需的部分的船（我使用以前在3ds Max制作的掩模圖幫助我選擇區(qū)域并掩蓋） 。 我基本上做了藍色的變化，一些黑色的片段和一些不同的灰色調(diào)。

這種情況下的顏色代表金屬上的油漆，所以粗糙度圖應(yīng)該在所有顏色中都是相同的，即使我更喜歡添加一些變化來打破均勻性。

金屬圖現(xiàn)在全都是黑色的，因為我還沒有制造任何原料。

Step 07: Add metal textures

Once I set up all the colors, I move on to add the metal textures. I choose one metal map from www.textures.com as my base metal and duplicate it to fill the whole canvas. I use it in Overlay blending mode to get a very subtle effect.

On top of this, I add a scratch map (also found in www.textures.com, and modified by me) at 60% opacity so the scratches are not very strong and evident in the render.

In the roughness map, I desaturate the metal texture and use it in Multiply mode. I also move the arrows inside the Blending Mode option window so only the darker tones remain visible. I want the metal texture to be dark here, so these areas look shinier. For the scratch map, I invert the colors so they become black and use it in Multiply mode.

I use a similar process for the metalness map to make it white (suggesting the metal underneath is the paint colors) and I duplicate the scratch map several times in Screen mode to get them very white.

步驟07：添加金屬紋理

一旦我設(shè)置了所有的顏色，我繼續(xù)添加金屬紋理。 我從www.textures.com選擇一個金屬地圖作為我的基礎(chǔ)金屬，并復(fù)制它以填補整個畫布。 我在Overlay混合模式中使用它來獲得非常微妙的效果。

除此之外，我添加了一個刮痕圖（也可以在www.textures.com中找到，并由我修改）以60％的不透明度，因此劃痕在渲染中不是很強大和明顯。

在粗糙度圖中，我使金屬紋理去飽和，并以“乘法”模式使用它。 我也在混合模式選項窗口中移動箭頭，因此只有較暗的色調(diào)保持可見。 我希望這里的金屬紋理變黑，所以這些區(qū)域看起來更加光滑。 對于劃痕圖，我反轉(zhuǎn)顏色，使其變?yōu)楹谏�，并以“乘法”模式使用�?/p>

我使用類似的金屬圖的過程使其變?yōu)榘咨�（建議下面的金屬是油漆顏色），并且我在屏幕模式下復(fù)制了幾次刮刮圖，以使它們變得非常白。

Step 08: Adding the panels map

To add even more variation to the different colors, I add a panel texture from Total Textures v7: Sci-fi. I use it in Overlay with a very low opacity and modify the Levels to add more contrast. I only use this map in some blue areas, so I make a mask to specify it.

For the roughness map, I desaturate the map and use it at very low opacity, tweaking Levels for more contrast. The metalness map remains unaffected by the panels. I also convert the desaturated map into a normal map to create more distinctions in the render.

At this point you should feel that the ship is made of metal and has been painted, and the damage should look natural. If it doesn't, go back and play a bit with the albedo, roughness and metalness maps, changing the values and balance of colors, and so on. In this tutorial I'm showing you the final result, my final colors and roughness values, but they took me a lot of time and testing until they looked good and natural. Feel free to change them as much as necessary until they give you a great result.

步驟08：添加面板圖

為了增加不同顏色的變化，我從Total Textures v7：Sci-fi添加一個面板紋理。我在Overlay中使用它，具有非常低的不透明度，并修改Levels以增加更多的對比度。我只在一些藍色區(qū)域使用這個地圖，所以我做一個蒙版來指定它。

對于粗糙度圖，我使地圖去飽和，并以非常低的不透明度使用它，調(diào)整等級以獲得更大的對比度。金屬圖保持不受面板的影響。我也將不飽和地圖轉(zhuǎn)換為法線貼圖，以便在渲染中創(chuàng)造更多的區(qū)別。

在這一點上，你應(yīng)該覺得這艘船是用金屬制成的，已經(jīng)被涂了，而且這種傷害應(yīng)該是自然的。如果沒有，回去玩一下反照率，粗糙度和金屬圖，改變顏色的價值和平衡等等。在本教程中，我向您展示了最終的結(jié)果，我的最終顏色和粗糙度值，但他們花了很多時間和測試，直到它們看起來很自然。隨意更改他們，直到他們給你一個很好的結(jié)果。

Step 09: Making the emissive map

Once I've got all the colors, panels, metal and scratches, the ship's starting to take shape in terms of shaders/materials. It looks metallic and a bit damaged.

Before I continue adding the peeling, dust and rust, I'll first create the emissive map. The emissive map always adds that extra layer of detail and visual interest to the model, creating areas that emit light. I always like to add some lines and dots here and there, and it also looks good to paint the windows and engines and make them glow.

To make the emissive map, I create a black solid color as the base layer, and on top of this one I add the emissive color layer (in this case, blue). This blue layer has a mask where I start to paint all the areas I wanted to glow. (I use the UV template in Screen mode as a guide to paint.)

步驟09：制作發(fā)射地圖

一旦我得到了所有的顏色，面板，金屬和劃痕，船只開始在著色器/材料方面形成。 它看起來很金屬，有點損壞。

在我繼續(xù)添加剝皮，灰塵和銹蝕之前，我先創(chuàng)建放射性地圖。 發(fā)射圖總是將額外的細節(jié)層次和視覺感興趣添加到模型中，創(chuàng)建發(fā)光的區(qū)域。 我總是喜歡在這里和那里添加一些線條和點，并且也可以繪制窗口和引擎并使其發(fā)光。

為了制作發(fā)射地圖，我創(chuàng)建一個黑色的純色作為基礎(chǔ)層，在這一個之上，我添加了發(fā)光色層（在這種情況下是藍色）。 這個藍色的層有一個面具，我開始畫出我想要發(fā)光的所有區(qū)域。 （我在屏幕模式中使用UV模板作為繪畫指南。）

Step 10: Adding peeling to the borders

Finally, the peeling, my favorite part. I need to be extra careful when making the peeling because I always add too much and then the model starts to look super destroyed; I end up deleting a lot of what I had already painted. (In any case, my models always look destroyed!) So whatever the goal you want for your model, whether you want it to look old and damaged or only have a bit of peeling damage, this is a very fun step.

Nowadays there are some techniques to obtain this effect quickly: for example, using curvature maps or Substance Designer. However, I'm still a big fan of painting by hand because I like to have full control of what I want to do and where exactly I want to do it. Using one technique or another will alway depends on your time constraints. In this tutorial I will share how I do this completely by hand.

For the albedo map, I create a dark-gray solid color layer and use a dry brush to start masking the borders of the panels. Remember that the value of gray determines the reflectance of the metal in the metalness map. I want the peeling to look bright, but not much, so I test some different gray values until I get the result I want.

In the roughness map, I use a very dark-gray because I want the surface to look smooth, since it's the raw metal that's been revealed underneath the paint. Finally, for the metalness map, I use a very light-gray, almost white.

Even if I use PBR and start using real material values, I change them a bit to fit my own tastes.

步驟10：添加剝離到邊界

最后，剝皮，我最喜歡的部分。因為我總是添加太多，所以我需要特別小心，然后模型開始看起來很厲害。我最后刪除了很多我已經(jīng)畫了。 （在任何情況下，我的模型總是看起來被毀壞�。┧�以無論你想要什么樣的模型，無論你想要它看起來老，損壞還是只有一點剝離傷害，這是一個非常有趣的一步。

現(xiàn)在有一些技術(shù)來快速獲得這種效果：例如，使用曲率圖或物質(zhì)設(shè)計器。然而，我仍然是手繪畫的粉絲，因為我喜歡完全控制我想要做的，以及我想要做的事情。使用一種或另一種技術(shù)將取決于你的時間限制。在本教程中，我將分享我如何完成這一切。

對于反照率圖，我創(chuàng)建一個深灰色的純色層，并使用干刷來開始屏蔽面板的邊框。請記住，灰度值決定了金屬圖中金屬的反射率。我想要剝皮看起來很亮，但不是太多，所以我測試一些不同的灰色值，直到我得到我想要的結(jié)果。

在粗糙度圖中，我使用非常深灰色，因為我希望表面看起來光滑，因為它是在油漆下面露出的原始金屬。最后，對于金屬圖，我使用非常淺灰色，幾乎是白色的。

即使我使用PBR并開始使用真正的材料價值，我改變了一點，以適應(yīng)我自己的口味。

Step 11: Decals

After the hard work of painting all the peeling, let's take a rest to add some decals, like the yellow bands on the sides and some logos. As usual, I create a solid color layer (yellow this time) and mask in the areas where I want the bands and logos to be. To give the worn feeling of the yellow paint, I modify some blending options in the Layer Style window.

In the roughness map, I use a light-gray to get a rough result. As I said before, it needs to be tested several times to get the desired result. The metalness map remains unaffected.

步驟11：貼花

在畫所有的剝皮的努力之后，讓我們休息一下，加上一些貼花，像兩邊的黃色條紋和一些標(biāo)志。 像往常一樣，我創(chuàng)建一個純色層（這次是黃色），并在我想要的樂隊和標(biāo)志的區(qū)域掩碼。 為了給出黃色油漆的磨損感，我在“圖層樣式”窗口中修改了一些混合選項。

在粗糙度圖中，我使用淺灰色來獲得粗略的結(jié)果。 如前所述，需要進行幾次測試才能獲得所需的結(jié)果。 金屬圖保持不受影響。

Step 12: Adding rust

For the rust effect, I want to add some orange/reddish patches around the model, but I don't want to paint them by hand, so for this one I use a burnt texture from Total Textures v19: Destroyed & Damaged. At first glance, the chosen map doesn't have the characteristics I want, but with a bit of manipulation in Photoshop I obtained exactly what I'm looking for.

I first copy the map around all the canvas, then put it in Color blending mode and play with the blending options inside the Layer Style window. At this point I've got the reddish patches I want, but they're missing contrast, so I make some Levels adjustments and it's done. I copy the same layer with all its blending adjustments (without the Levels adjustment) to the roughness map, but I need it to be white so I desaturate the map and set it to Color Dodge mode.

For the metalness map, I again copy the layer with its blending adjustments, but this time I use it in Subtract mode to have it in black. It is almost invisible to the eyes if you look at the metalness map, but the rust texture is there doing its job.

步驟12：加銹

對于防銹效果，我想在模型周圍添加一些橙色/微紅色的補丁，但是我不想手工繪制，所以對于這一個，我使用Total Textures v19：被破壞和損壞的燒焦紋理。乍一看，所選地圖沒有我想要的特點，但是在Photoshop中進行了一些操作，我獲得了正在尋找的內(nèi)容。

我首先在所有的畫布上復(fù)制地圖，然后將其放入色彩混合模式，并在“圖層樣式”窗口中播放混合選項。在這一點上，我已經(jīng)得到了我想要的紅色補丁，但是他們沒有對比，所以我做了一些Levels調(diào)整，完成了。我將所有混合調(diào)整（沒有Levels調(diào)整）復(fù)制到粗糙度圖上，但是我需要它是白色的，所以我去掉了地圖并將其設(shè)置為Color Dodge模式。

對于金屬圖，我再次使用混合調(diào)整來復(fù)制圖層，但是這次我在減法模式下使用它來使其變黑。如果你看著金屬圖，幾乎看不見，但是生銹的紋理是在做它的工作。

Step 13: Dirt pass

I don't paint the dirt by hand, and I don't use any texture for it either. On this occasion, I use Substance Designer to generate the dirt. In Substance Designer, I first create a Metalness/Roughness Graph. I add a Metal Weathering filter and only choose the Base Color input. I link a white color to the Base Color input and link the ship's ambient occlusion map in the Ambient Occlusion input. That's all I need here to generate the dirt, so, in the Effect rollout of the Weathering filter, I play with the Dirtiness parameter until I've achieved a nice result. I export the Base Color output here and am ready to start working in Photoshop once again. (See image 13a.)

Now I'm back in Photoshop with the new dirt map. It looks nice in Multiply mode, but the dirt wouldn't be black, so to add some color to the new map I apply an orange/brownish solid color to it. I also add it in Multiply mode to the metalness map.

For the roughness map, I need to invert the colors of the map, so the black dirt becomes white and I use it in Screen blending mode. (See image 13b.)

步驟13：污跡

我不用手畫污垢，我也不用任何紋理。在這種情況下，我使用物質(zhì)設(shè)計器來產(chǎn)生污垢。在物質(zhì)設(shè)計師中，我首先創(chuàng)建了一個金屬/粗糙度圖。我添加一個金屬風(fēng)化過濾器，只選擇基色輸入。我將一個白色的顏色鏈接到基本顏色輸入，并在“環(huán)境遮擋”輸入中鏈接船舶的環(huán)境遮擋圖。這就是我需要在這里產(chǎn)生污垢，所以，在“風(fēng)化”過濾器的“效果”展開中，我玩Dirtiness參數(shù)，直到我取得了不錯的結(jié)果。我在這里導(dǎo)出Base Color輸出，并準(zhǔn)備好再次在Photoshop中開始工作。 （見圖13a）

現(xiàn)在我回到Photoshop的新的污垢圖。它在“乘法”模式下看起來不錯，但污垢不會變黑，因此為了向新地圖添加一些顏色，我將使用橙色/棕色純色。我也將它添加到“乘法”模式到金屬圖。

對于粗糙度圖，我需要反轉(zhuǎn)地圖的顏色，所以黑色的污垢變成白色，我在屏幕混合模式下使用它。 （見圖13b）