Over the course of this extensive 7 day series. Shray Khanna will guide you through the entire process of creating a next-gen, low poly vehicle using Maya and Photoshop. Throughout the series, Shray covers the complete next-gen pipeline in detail. In day 6 we'll begin the texturing process by creating a detailed Diffuse map using Adobe Photoshop.
Also available in this series:
- "Next-Gen Armored Car" Day 1
- "Next-Gen Armored Car" Day 2
- "Next-Gen Armored Car" Day 3
- "Next-Gen Armored Car" Day 4
- "Next-Gen Armored Car" Day 5
- "Next-Gen Armored Car" Day 6
- "Next-Gen Armored Car" Day 7
To get started with the diffuse texturing, the first thing that we need is our UV snapshot, so that we'll know what needs to be painted and where. So for that select your armored car model and in the "UV texture editor" go to Polygons>UV Snapshot.
Now in the UV snapshot window change the "Size X" and "Size Y" to 2048 for each, and the "Image format" to "Targa". And then save the file as "UV".
Now open the file in Photoshop along with the Normal and Occlusion maps we created earlier, then press and hold the Shift key and click and drag the "UV" layer onto the "Normal Map" (1). By doing this the UV layer will be transferred to the Normal map PSD, and by pressing the Shift key it will make sure it's transferred in it's correct position. Now select the new UV layer in the Normal Map PSD, and change it's "Blending mode" to Screen (2).
Now that the Blending Mode is changed, select the same layer in the Normal Map and again by pressing and holding the Shift key, drag it onto the Occlusion.
Now save this Occlusion as a .psd file and name it "Diffuse". We'll keep this for future use, as we want our occlusion to be intact and we'll be creating our textures using this PSD only. Now select the 4 layers of the occlusion map and press Ctrl+E (1), this will merge all the selected layers into one layer (2).
Now we'll fill in the base colors so it will become easier to differentiate between materials, so go to the left toolbar and click on the color picker, and select a dark, desaturated tone of yellowish green (1). At this stage it doesn't need to be too specific, as we'll be changing it again in the future as new textures and tones are added. Now create a new layer by clicking on the second to last icon in right corner of the layers window. And fill the new layer with the selected Green color by pressing Alt+Backspace (the Shortcut to fill using the foreground color). Then by double clicking on the name of the new layer, change it's name to BG (BackGround) (2).
Now select the Occlusion layer and set it's "Blending mode" to Multiply and lower the "Opacity" to 90%.
Rename this occlusion layer "Occlusion" for future reference (1), and then duplicate the layer by pressing Alt and dragging the layer (in the layer window only.) Set the duplicated layer's "Blending mode" to Soft Light and adjust the "Opacity" to 33% (2).
Now create another new layer, and rename it "Black" (1). Pick the foreground color again and choose a lighter tone of black (2). Then using the "Rectangular Marquee Tool" (M) make a selection of all the parts that will be black. You can change the "Marquee Tool" from "Rectangle" to "Elliptical" by pressing Shift+M. Use this to select the round wheel shapes, and then fill them with same black color (3).
Now create a new layer and rename it "Grey" (1), and then change the foreground color to neutral Grey color (2). Now make the selection shown below in image 3 and fill it with this color.
Now we also need to check it side by side in Maya to see how it's coming, so back in Maya go to "Hypershade" and select the Occlusion texture file (1), browse again and select the "Diffuse".psd we saved out earlier from Photoshop (2). Now we can view the model with the updated texture in realtime (3).
Now back in Photoshop, select the center portion of the wheel and delete it from the "Black" layer, as this is part of the alloy and should only be the base color.
Now we have to correct a few artifacts that come along with the occlusion map. For that, select an unaffected area near it (about the same dimensions) and move it over the affected areas as shown in these 2 examples.
Now to get rid of the entire shovel and it's belt shadows, first create a selection using the "Polygonal Lasso Tool" (L)(1), then select the "Rectangular Marquee Tool" by pressing M and move only the selection to the unaffected area on the other side. Then "Right click" and select "Transform Selection" (2), you'll notice that a transformation box appears around it, "Right click" again and and select "Flip vertical" (3), and then move it to fit in the space required (4).
Now with the same selection press Ctrl+J, which will separate the selection into a new layer (1). Move that layer over the shovel shadow and Transform it by pressing Ctrl+T, then "Right Click" and select "Flip Vertical" (2). Now erase the outer edges of this layer, and copy the belt shadow from one side to other side (3-4).
Next select the round hatch and rotate it using the transformation gizmo (Ctrl+T) so that the line is straight (1), and then deselect the half of the hatch that contains the white line by pressing Alt and selecting it (2). Then duplicate the selected half by pressing Alt and moving it with the "Move Tool (V)" to the other side of the hatch. Transform it again (Ctrl+T) and then "Flip vertical" (3) to make the full circle again (4).
Now create another new layer and name it "Brown". Then choose a brown color and fill the selected areas shown below.
To proceed further we'll be needing a texture library which contains some basic textures, in our particular case we'll be needing metal textures the most. So here is my very own collection of various metal textures which I've collected (1), most of these are from www.cgtextures.com which provides a very good collection of basic textures. The best part is that one can download 15mb of textures a day for free. (you can also find many other sites online that provide free textures.) Out of all these textures I have chosen these five (2).
To get started press Shift and drag one of the metal texture into our diffuse psd, then transform it by pressing Ctrl+T and then "Right Click" and choose Rotate 90 CW (1) because we want all the scratches horizontally. Place it in the corner and press Enter to keep your transformations as it is (2). Now keeping the same selection, and using the "Move Tool" (V) press Alt to duplicate the selection (in the same layer), and place it in the other corner (3).
Now repeat the same procedural and completely fill the layer with the metal texture (1). You'll notice that there are now visible horizontal and vertical seams because of the duplicated texture. So to remove them, select the horizontal seams first and select the "Patch Tool" (J) (2), and move the selected area to another area which doesn't have a visible seam. The tool will replace the seams texture with the one from the unaffected area, and the seams will be resolved (3). Repeat the same procedure with the vertical seams too.
Now select the same metal layer, and click on the "Blending Modes" option box (1), change the "Blending mode" of this layer from "Normal" to Overlay (2). Also check the outcome again in Maya, as we can see in the last image, the size of the scratches is too big (3), so we have to change it once more to get the proper look.
Back in Photoshop, select the metal texture layer and resize it to have smaller scratches using transform (Ctrl+T), save the file and check it in Maya by reloading the texture again in attribute editor.
Now add a second metal texture and resize it to have the proper scale (1), and then duplicate the selection to fill the page (2). Finally using the "Patch Tool" (J), as shown before get rid of the seams (3). Also set the "Blending Mode" to Overlay and the Opacity to 32%.
Now grab another metal texture and place it in the corner (1). Following the same procedure, fill the layer and remove any seams to complete the texture. Then set it's "Blending Mode" to Hue (2).
Now check the model again in Maya by reloading the texture. There are two errors which are most visible in the viewport, one is the diffuse color of the turret which is lighter than the body (which we will have to tweak in the Diffuse texture itself.) And the other is the two black knobs, but this problem is on the normal map because we can see our Diffuse map doesn't have these black colored knobs in the texture, so we'll correct it later.
Back in Photoshop select the topmost "Overlayed" metal layer, and select the turret area of the texture. Using the "Patch Tool" (J) replace the selection with some darker area and that will solve the lighter turret issue (1). Now make a selection on the "Brown" layer and select the metal texture layer with the "Hue" "Blending Mode" and then delete it using the same selection (2).
Now that the hue layer has been deleted from the selection we have our brown color back. But now the overall tone of the green is a bit lighter the what we need (1), so select the BG layer and by using "Hue/Saturation" (Ctrl+U or alternatively Image>Adjustments>Hue/Saturation...) make it a little darker by decreasing the lightness value with the slider (2).
The texture we have right now is very noisy because of the blended metal textures. The original Armored Car material isn't very grainy, so we need to adjust the opacity of some of the layers, as shown below.
Now add another metal texture and fill the layer (1), and then using the "Patch Tool" (J) remove the seams (2). Finally, set the blending mode to Overlay and the opacity to 64% (3).
Now add another metal grain textures to have some detailed metal, and have it's blending mode to "Hard Light" and opacity to "75%" , then select the same layer and go to " Image>Adjustments>Levels (Ctrl+L)" and also alternatively access levels by just pressing "Ctrl+L" as shown, then move the right most slider of white color a little towards left till the value of "230". And then have a look at the texture on vehicle in Maya by "Reloading" it.
Now a few parts of the brown need a different tone, so make a selection of those parts, and with the "Brown" layer selected, press Ctrl+U for "Hue/Saturation", then change the values as shown.
Now we need to apply some light texture to our headlights and taillights, so for that I have searched my personal library of images collected from various sites on the web, and I have selected these 3 textures which are suit the vehicle.
Now using the "Elliptical Selection Tool", select and place these lights texture in their respective places (over their UV's) using move and transform to scale (1). Then reload the texture in Maya and check the placement of all three lights (2)(3)(4).
Now we need to add some details to the gun nozzle, so make a circular selection and fill it with a black color on a new layer (1). Then place the same shape adjacently, by duplicating the shape in same layer. Then select all the shapes and duplicate them again and place them below and diagonally to the upper ones (2)(3).
Now place them like this by duplicate the pattern we just created.(1). Now "Right click" on the layer (2) and select "Blending Options" (3) .
Now in the new window, select the "Outer Glow" tab (1) and click on the color box, in the color picker window change the color to white (2). Then change the opacity to 53%, and the size to 1px (3). Press OK to save your changes.
And here's a view in Maya after reloading the textures.
Now we need one more occlusion pass for the vehicle because of a few drawbacks with the X-normal occlusion map. So we'll be using 3ds Max 2009 (other versions will also work the same way) for this, as Max is pretty fast and easy to get the desired results. So open Max, and go to File>Import (1), and import the "Main_Body_Low.obj" first (2).
And this will open a new window of "OBJ Import Options", just click on Import to have your mesh keep all the options intact (1). If a summary log came stating errors, just ignore them and click on Close (2).
Now in your "Modifier List" you'll see "Editable Mesh"(1). "Right click" on the modifier and select "Editable Poly" to convert the mesh to polygons (2). Now select "Element" mode from the selection options and press Ctrl+A to select all (3).
"Right click" anywhere under the selection tab, and select "Polygons Smoothing Groups"(1) and it will land you directly in it's properties (otherwise you have to scroll your way down in the tab to find it) So once in the "Polygons Smoothing Groups" properties, click on "Clear All" (2) to remove all the present applied smoothing groups, change the smoothing angle from 45 to 35, and press "Auto Smooth" (3). This will apply smoothing groups to the surface depending on the angles, this should pretty much work for us now.
Now save the file so we have a backup, and name it "Car_Occlusion".
Now Import the "Turret_Low.obj"(1) and apply smoothing groups by following the same procedures as before (2). Repeat the same process once again for the "Small_Parts_Low.obj" (3).
Now a few parts don't get proper smoothing because of more roundness and lower polygons, so for those parts, select them in "Element" mode, and increase the smoothing angle to 45 first, then "Auto Smooth" them again. Then again select the ones with lower poly distribution and set the smoothing angle to 75, this time and it will soften all selected.
Now Import the "Wheel_Low.obj" and apply the same smoothing groups with a smoothing angle of 45.
Now go to File>Import again and select the "Armored_Car_High.obj" (1), in the "OBJ Import Options" window, check the option box for "Import As A Single Mesh", this will merge all the meshes into one and then just hit "Import" (2).
Now all the meshes are imported and you still have that selection of only the High poly imported meshes, so "Right Click" and select "Hide Selection", this will hide every selected mesh and will make your scene lighter and easier to move around in.
Now also select and Hide the wheel, then drag select all three remaining meshes. Then press 0 to open the "Render to Texture" window, (which we'll be generating our Occlusion map with). Now these three meshes are added in the objects tab (1). So now "Right click" in the viewport and select "Unhide All". As we'll be needing our high polygon meshes to project (2).
Now in the "Render to Texture" window, under the "Projection Mapping" tab. Click "Enable" first and then click on "Pick...". This will open a new window called "Add Targets". Select the High polygon mesh (which in this case is named "polysurface 1829" ) and then click "Add".
Now in the "Render to Texture" window, under "Mapping Coordinates". Select "Use Existing Channel". So that it will generate the UV's according to those UV's only, and not create new UV's
Now go to the "Render Setup" options button, and open the "Assign Renderer" options tab (1). Under the "Production" tab, select "Choose Renderer" and in the newly opened window, select "Mental Ray Renderer" (2).
Now back in the "Render to Texture" window. Select "Add", and choose "Ambient Occlusion [MR]", and then hit "Add Elements" (1). Now select the size of the output map required. In our case it is "2048x2048" (2).
Now change the "Samples" to 128 and then hit the "Render" button (1). You'll see the constructive progress in the new opened window (2).
Now all the generated textures are being placed in a default folder under My documents\3dsmax\sceneassets\images, here are our 3 generated textures.
Now drag the 3 textures into Photoshop and by using alpha selections (1), compile all 3 into a single texture (2).
Now bring this layer into our "Diffuse.psd", and rename it "Occlusion_Dark". Then set it's blending mode to "Multiply" with an opacity of 94%.
Now check the model in Maya, and you'll see the increased depth added into the texture itself. But there are a few artifacts, so we need to fix these in the texture.
Now select the area which was not aligned properly, and move it forward as much as required (1). Do the same with the other set (2), and also move the other shadow selection a bit too (3).
Now remove this particular artifact (1), by erasing it from the map (2).
Now there are few areas of the shovel which were left, so select the "Grey" layer (1) and fill the selections with a grey color (2).
Now select all the metal texture layers, and press Ctrl+G to make a group of the selected layers.
Now duplicate this group using "Alt"(1), and select the bottom layer of this group. Change it's blending mode to "Normal" and leave it at 100% (2). Then again select the group and press Ctrl+E to merge all the layers into one (3).
Now move this layer just above the base color.
Now select the same layer and create a mask by clicking on the icon shown.
Now go to the "Brush" and select the "Noisy Brush" with a size of 24.
Now select the "Brushes option box" ( this will open the option window for the brush), select "Brush Tip Shape" and enable "Spacing" by checking the box. Increase it with the slider to 54% (1). Then move to the "Shape Dynamics" tab and increase the "Size Jitter", "Angle Jitter", "Roundness Jitter" and "Minimum Roundness" to the values shown in the image using the sliders (2).
Now move to the "Scattering" tab and increase the "Scatter" amount to 99% (by using the slider or by entering the value)(1). Now move to the "Brush Tip Shape" tab again, and decrease the "Spacing" a bit (2).
Now select the "Dual Brush" tab, and select the faded brush, with a size of 25 (1). Keep the other values as shown in the image and then move to the "Other Dynamics" tab and increase the "Opacity Jitter" and "Flow Jitter" to 16%, finally change the "Control" to "Off" (2).
Now select the small "option box" near the Brush icon. In the new window, click on the "save brush" icon on the right, and then name your brush and save it (1). Now again select that icon and in the window, select your newly created brush (2).
Now select the mask from the layer itself, and change the "foreground color" to white (1). Using our new brush, paint over the edges where they're most likely to get worn. (mostly on the corner edges) (2)(3).
Follow the same procedure for any worn edges.
Follow up of the same paint over procedure.
Also be sure to check the model in Maya to have a idea of how it will look.
Now also add some random straight strokes for scratches, as it will depict some wear and tear on the surface. Complete all the worn edges following the same procedures.
And here is the final result with all the scratches applied to the surface.
Now select another "noisy brush" with a size of 39 (1). Then go to the "Brush Options" and under "Scattering", increase the "Scatter" amount to 99% (2).
Now change the foreground color to a reddish brown with a less saturated tone, and change the "Brush Mode" to "Soft Light", the opacity to 69%, and the flow to 50%. Then create a new layer and start painting over the surface wherever you want to have dirt. Also rename this new layer to "Dirt".
Now follow the same paint over procedure to cover the various parts where you thinks dirt would accumulate. Now select all the layers below the "Dirt" layer, and by pressing Ctrl+G, make them a group. Then duplicate the group and merge it into a single layer by pressing Ctrl+E. This will make your PSD file a little lighter to work with.
Following the same footsteps, this paint over was done on all the parts which will have dirt (In this case every part has dirt and rust).
Now some final color tweaks needs to be done to get the proper feel. For this, click on the lower most icon in the layers window (next to the "Masking" icon) and you'll notice all the "Adjustments mode" are available. Select "Hue/Saturation..." and add the values shown in the 2nd image. Make sure that the newly created "Hue/Saturation" layer is above all the other layers. The plus side of using this as a layer, is that you can tweak it anytime you want to.
Now in the same way, add a "Levels" and match the values shown in the image.
Now choose another brush with a size of 17 from the list (1). Set it's opacity to 54% and it's flow to 50%. Then create a new layer and rename it "Dark", and keep it's blending mode set to "Soft Light" and it's opacity set to 76%. Then paint the selection shown with a black color (2).
Now in the Tool's window, select and hold down on the "Line Tool (U)" and change it to "Custom Shape tool (U)"(1). Then in the Options bar select the icon next to the shape and it will open the shape selection window, here select the "triangle" icon and select "All" (2), this will append all the shapes in the window.
Now select the "Triangular" shape with round corners (1), and while pressing shift, drag it over the texture (2). Then "Right click" on it and select "Make Selection" (3).
Now in the "Make Selection" options window, keep the "feather radius" set to 0, and keep the "Operation" as "New Selection" only (1). Then change the foreground color to white (2). Create a new layer and fill the selection with the foreground color by pressing Alt+Backspace (3).
Now duplicate this layer, and press Ctrl+I to invert the color of the layer so that black will become visible over white (1). And then using "Transform" (Ctrl+T ), scale the layer down a bit (2). Then make a selection of the layer by pressing Ctrl and clicking on the layer (3).
Now select the main layer and delete the selection from it, also delete the scaled triangle layer (1), then using Transform, tilt the triangle shape a bit (2). Then in the Tool bar select "Text" and click at the triangle shape's center Now change the font to Stencil Std type, to Bold and the size to 24pt (3).
Now write "44" with the "Text Tool". Then using Transform, align it with the triangle shape (1), now merge the text layer and the shape layer into one layer, and then duplicate it and place it on the other side of the turret (2). Finally merge them together using Ctrl+E and then rename this layer "44" (3).
Now on the front wheel arch, make a rectangular selection (1). Then using the "Polygonal Lasso tool (L)", make a selection as shown in the 2nd image (2), then change the foreground color to a desaturated tone of Red (3).
Now fill this selection in a new layer (1), then deselect the right side by using the "Marquee selection tool (M)' while holding Alt (2). Then go to Select>Modify>Contract and set the size to 5 pixels (3).
Now you have the required selection (1), so set the foreground color to a light blue color and then fill the selection (2). Now press B for brush, then "Right click" and select the size 9 brush (3). Paint an eye shape over it and then rename this layer to "Eye-Icon" (4).
Now on the left rear wheel arch, make a rectangular selection. Create a new layer and fill it with the same light blue color (1). Then make another rectangular selection over it, and fill it with the white color (2). Then using the "Text Tool(T)", write "44" over it (3).
Now change the font to Palatino Linotype (1), and then using Transform, right click and select Rotate 90 CW. Place the text over the shape as shown (3).
Now again using the "Text Tool (T)" select the font type Consolas, and write "HENGIST" (1), and place it on the front portion (2). Then using the font type Stencil Std, write "F225349" (3).
Now place this text just below the one before. Then again using Text, write "AUDEHER" in the same Stenil Std font (1), and place it on the side of the car (2). Make a copy of it and using Transform place it on the other side as well (3).
Now select all the text and icons layers and press Ctrl+G to group them, Rename this "TEXTs" (1) . Now make another copy of this group (2) and then merge it to a single layer by pressing Ctrl+E, then set it's blending mode to Overlay (3).
Now apply a mask to this layer and select the "Eraser Tool (E)" (1). And select any noisy brush, then start erasing the text layer here and there randomly, just to add a used and chipped off paint feel to it (2)(3).
Here is the preview in Maya with the Diffuse and Normal maps applied.
Now change the foreground and background colors to "Purple" and "Blue", then create a new layer and place it above all the other layers. Then go to Filter>Render>Clouds (1) , this will fill the layer with the two colors (2), finally change the blending mode to Pin Light (3).
Now Press Ctrl+A to select all, then press Ctrl+Shift+C to copy all, and finally press Ctrl+V to paste. You will now have all the diffuse in a single layer. Now go to Filter>Other>HighPass (1) , in the option window set the radius to 0.8 (2), and then rename this layer "Details" and set it's blending mode to Overlay (3). This will add some fine details to the texture.
Now again press Ctrl+V to paste the layer, then press Ctrl+L to adjust the "Levels", match the values shown in the 1st image (1). Then add another "Hue/Saturation" adjustment "over it (2) and give it the values shown in image 3 (3). Save this out as "Armored_Car_Specular.tga".
Now again paste the layer and go to Filter>Nvidia Tools>NormalMapFilter...(1) (Now the Nvidia tools filter is not a default filter in Photoshop, but it is widely used for creating game art and is also freeware. You can downloaded from http://developer.nvidia.com/nvidia-texture-tools-adobe-photoshop, (it's very easy to install). Now in the options window, keeps the settings as shown, and hit Enter (2). Now drag this layer to the Normal map PSD and set it's blending mode to Overlay (3) . Save this as "Normal_Map.tga".
Now bring the specular texture file into Maya and apply it under the "SpecularColor" of the material (1). Also reload the Normal map texture (2).
And here are some screen grabs from the Maya viewport showing the ample level of specular on the surface.
Now just one final tweak for the specular. Duplicate the "Scratches" layer and place it over the "Level" layer, change it's blending mode to Linear Light and save the tga file again.
And here is our Low poly model with the Diffuse, Normal and Occlusion maps applied. (Maya High quality viewport grabs only).