Water Rendering
Water rendering is easy to achieve in Awakening. You first use a Portal or Ocean to generate reflected / refractive images, the use water shaders to compose them.
All shader files for water rendering can be found at the "effects\water" folder.
Shader File |
Preview | Explanation |
| bump_nops.sha | Use a bump map to distort reflected / refractive
image. Factor: number bump_texture number reflected_texture number refractive_texture vec4 vecWaterNormal -- the normalize normal vector of water surface vec4 vecWaterParam -- x : wave speed Usage: material.setTexture(0, bump_texture) material.setTexture(1, reflected_texture) material.setTexture(2, refractive_texture) local waternormal=vec4.new(0,1,0) local wavespeed=0.2 material.setEffectVector('vecWaterNormal',waternormal) material.setEffectVector('vecWaterParam',vec4.new(wavespeed)) PixelShader: No |
|
| bump_norefra_nops.sha | Use a bump map to distort reflected image,
no refraction; fast than above shader. You should check material's Transparence style for this shader. Factor: number bump_texture number reflected_texture vec4 vecWaterNormal -- the normalize normal vector of water surface vec4 vecWaterParam -- x : wave speed Usage: material.setTexture(0, bump_texture) material.setTexture(1, reflected_texture) local waternormal=vec4.new(0,1,0) local wavespeed=0.2 material.setEffectVector('vecWaterNormal',waternormal) material.setEffectVector('vecWaterParam',vec4.new(wavespeed)) PixelShader: No |
|
| lake.sha | Compose reflected / refractive images
and water color by depth map, and use a bump map to distort
result. See Render scene depth info to a texture for depth map, and you need hide ocean self when rendering the map. Factor: number reflected_texture number refractive_texture number depth_texture number bump_texture vec4 vecWaterNormal -- the normalize normal vector of water surface vec4 vecWaterParam -- x : wave speed; y : bump strength vec4 vecWaterColor -- self color of water, used water color = vecWaterColor * vecWaterColor.a Usage: material.setTexture(0, reflected_texture) material.setTexture(1, refractive_texture) material.setTexture(2, depth_texture) material.setTexture(3, bump_texture) local waternormal=vec4.new(0,1,0) local wavespeed=0.2 local bump=2 material.setEffectVector('vecWaterNormal',waternormal) material.setEffectVector('vecWaterParam',vec4.new(wavespeed,bump)) local wateralpha=0.5 material.setEffectVector('vecWaterColor',vec4.new(.1,.4,.4,wateralpha)) PixelShader: 2.0 |
|
| lakeRipple.sha | Mainly same with lake.sha,
but also use a ripple map to plus the distort result. Factor: ( ... same with lake.sha here ) number ripple_texture -- the ripple texture essentially is a height map vec4 vecUVRipple -- uvRipple = uvBump* vecUVRipple.xy + vecUVRipple.zw number fRippleStrength Usage: material.setTexture(4, ripple_texture) --
sample codes for using ripple map |
(Remark: if use the lake.sha
or lakeRipple.sha, you needs use
Back Buffer Aligned render target for
reflected / refractive / depth map, and do not
check RTT's 'Consistent with back buffer'
style.)
Workflow:
1. Create a surface as water
2. Create a portal on the surface
3. Add two render targets
Right-Click in the Texture Browse Window, select "Add Render
Target" from the context menu. Then select a
image file in Open File Dialog. Please ensure the image width is same as height
(square image). Do same for
another render target.
4. Select render targets
Select the portal, in the Render To Texture rollout of portal panel, select
one render target; and check 'Consistent with back buffer'
style. Click the 'Actions'
button, add two actions:
| Message | Function | Object |
| Render Texture Begin | Hide | water surface |
| Render Texture End | Show | water surface |
In the Render To Texture (Mirror) rollout, select
another render target, and do same as above.
5. Add bump texture
Right-Click in the Texture Browse Window, select 'Add Bump Texture' from the context menu. Then select
"textures\wave_height.png" in Open File
Dialog.
6. Create material
In the Material panel, new a material; set 1st texture to the bump texture;
set 2nd texture to the render target in RTT(Mirror); set 3rd texture to the
render target in RTT; load shader file "effects\water\bump_nops.sha".
6. Assign the material to water surface
Please ensure no texture assign to water surface. You can use UV Tool to
adjust water surface's texture coordinates for changing wave size.
( if use bump_norefra_nops.sha, no need the 3rd texture; and only need set RTT(Mirror) in the portal. )
Tip: set Clip Offset for RTT of portal to avoid seams near bank.