class GPUFFT(DebugObject):
""" This is a collection of compute shaders to generate the inverse
fft efficiently on the gpu, with butterfly FFT and precomputed weights """
def __init__(self, N, sourceTex, normalizationFactor):
""" Creates a new fft instance. The source texture has to specified
from the begining, as the shaderAttributes are pregenerated for
performance reasons """
DebugObject.__init__(self, "GPU-FFT")
self.size = N
self.log2Size = int(math.log(N, 2))
self.normalizationFactor = normalizationFactor
# Create a ping and a pong texture, because we can't write to the
# same texture while reading to it (that would lead to unexpected
# behaviour, we could solve that by using an appropriate thread size,
# but it works fine so far)
self.pingTexture = Texture("FFTPing")
self.pingTexture.setup2dTexture(
self.size, self.size, Texture.TFloat, Texture.FRgba32)
self.pongTexture = Texture("FFTPong")
self.pongTexture.setup2dTexture(
self.size, self.size, Texture.TFloat, Texture.FRgba32)
self.sourceTex = sourceTex
for tex in [self.pingTexture, self.pongTexture, sourceTex]:
tex.setMinfilter(Texture.FTNearest)
tex.setMagfilter(Texture.FTNearest)
tex.setWrapU(Texture.WMClamp)
tex.setWrapV(Texture.WMClamp)
# Pregenerate weights & indices for the shaders
self._computeWeighting()
# Pre generate the shaders, we have 2 passes: Horizontal and Vertical
# which both execute log2(N) times with varying radii
self.horizontalFFTShader = BetterShader.loadCompute(
"Shader/Water/HorizontalFFT.compute")
self.horizontalFFT = NodePath("HorizontalFFT")
self.horizontalFFT.setShader(self.horizontalFFTShader)
self.horizontalFFT.setShaderInput(
"precomputedWeights", self.weightsLookupTex)
self.horizontalFFT.setShaderInput("N", LVecBase2i(self.size))
self.verticalFFTShader = BetterShader.loadCompute(
"Shader/Water/VerticalFFT.compute")
self.verticalFFT = NodePath("VerticalFFT")
self.verticalFFT.setShader(self.verticalFFTShader)
self.verticalFFT.setShaderInput(
"precomputedWeights", self.weightsLookupTex)
self.verticalFFT.setShaderInput("N", LVecBase2i(self.size))
# Create a texture where the result is stored
self.resultTexture = Texture("Result")
self.resultTexture.setup2dTexture(
self.size, self.size, Texture.TFloat, Texture.FRgba16)
self.resultTexture.setMinfilter(Texture.FTLinear)
self.resultTexture.setMagfilter(Texture.FTLinear)
# Prepare the shader attributes, so we don't have to regenerate them
# every frame -> That is VERY slow (3ms per fft instance)
self._prepareAttributes()
def getResultTexture(self):
""" Returns the result texture, only contains valid data after execute
was called at least once """
return self.resultTexture
def _generateIndices(self, storageA, storageB):
""" This method generates the precompute indices, see
http://cnx.org/content/m12012/latest/image1.png """
numIter = self.size
offset = 1
step = 0
for i in xrange(self.log2Size):
numIter = numIter >> 1
step = offset
for j in xrange(self.size):
goLeft = (j / step) % 2 == 1
indexA, indexB = 0, 0
if goLeft:
indexA, indexB = j - step, j
else:
indexA, indexB = j, j + step
storageA[i][j] = indexA
storageB[i][j] = indexB
offset = offset << 1
def _generateWeights(self, storage):
""" This method generates the precomputed weights """
# Using a custom pi variable should force the calculations to use
# high precision (I hope so)
pi = 3.141592653589793238462643383
numIter = self.size / 2
numK = 1
resolutionFloat = float(self.size)
for i in xrange(self.log2Size):
start = 0
end = 2 * numK
for b in xrange(numIter):
K = 0
for k in xrange(start, end, 2):
fK = float(K)
fNumIter = float(numIter)
weightA = Vec2(
math.cos(2.0 * pi * fK * fNumIter / resolutionFloat),
-math.sin(2.0 * pi * fK * fNumIter / resolutionFloat))
weightB = Vec2(
-math.cos(2.0 * pi * fK * fNumIter / resolutionFloat),
math.sin(2.0 * pi * fK * fNumIter / resolutionFloat))
storage[i][k / 2] = weightA
storage[i][k / 2 + numK] = weightB
K += 1
start += 4 * numK
end = start + 2 * numK
numIter = numIter >> 1
numK = numK << 1
def _reverseRow(self, indices):
""" Reverses the bits in the given row. This is required for inverse
fft (actually we perform a normal fft, but reversing the bits gives
us an inverse fft) """
mask = 0x1
for j in xrange(self.size):
val = 0x0
temp = int(indices[j]) # Int is required, for making a copy
for i in xrange(self.log2Size):
t = mask & temp
val = (val << 1) | t
temp = temp >> 1
indices[j] = val
def _computeWeighting(self):
""" Precomputes the weights & indices, and stores them in a texture """
indicesA = [[0 for i in xrange(self.size)]
for k in xrange(self.log2Size)]
indicesB = [[0 for i in xrange(self.size)]
for k in xrange(self.log2Size)]
weights = [[Vec2(0.0) for i in xrange(self.size)]
for k in xrange(self.log2Size)]
self.debug("Pre-Generating indices ..")
self._generateIndices(indicesA, indicesB)
self._reverseRow(indicesA[0])
self._reverseRow(indicesB[0])
self.debug("Pre-Generating weights ..")
self._generateWeights(weights)
# Create storage for the weights & indices
self.weightsLookup = PNMImage(self.size, self.log2Size, 4)
self.weightsLookup.setMaxval((2 ** 16) - 1)
self.weightsLookup.fill(0.0)
# Populate storage
for x in xrange(self.size):
for y in xrange(self.log2Size):
indexA = indicesA[y][x]
indexB = indicesB[y][x]
weight = weights[y][x]
self.weightsLookup.setRed(x, y, indexA / float(self.size))
self.weightsLookup.setGreen(x, y, indexB / float(self.size))
self.weightsLookup.setBlue(x, y, weight.x * 0.5 + 0.5)
self.weightsLookup.setAlpha(x, y, weight.y * 0.5 + 0.5)
# Convert storage to texture so we can use it in a shader
self.weightsLookupTex = Texture("Weights Lookup")
self.weightsLookupTex.load(self.weightsLookup)
self.weightsLookupTex.setFormat(Texture.FRgba16)
self.weightsLookupTex.setMinfilter(Texture.FTNearest)
self.weightsLookupTex.setMagfilter(Texture.FTNearest)
self.weightsLookupTex.setWrapU(Texture.WMClamp)
self.weightsLookupTex.setWrapV(Texture.WMClamp)
def _prepareAttributes(self):
""" Prepares all shaderAttributes, so that we have a list of
ShaderAttributes we can simply walk through in the update method,
that is MUCH faster than using setShaderInput, as each call to
setShaderInput forces the generation of a new ShaderAttrib """
self.attributes = []
textures = [self.pingTexture, self.pongTexture]
currentIndex = 0
firstPass = True
# Horizontal
for step in xrange(self.log2Size):
source = textures[currentIndex]
dest = textures[1 - currentIndex]
if firstPass:
source = self.sourceTex
firstPass = False
index = self.log2Size - step - 1
self.horizontalFFT.setShaderInput("source", source)
self.horizontalFFT.setShaderInput("dest", dest)
self.horizontalFFT.setShaderInput(
"butterflyIndex", LVecBase2i(index))
self._queueShader(self.horizontalFFT)
currentIndex = 1 - currentIndex
# Vertical
for step in xrange(self.log2Size):
source = textures[currentIndex]
dest = textures[1 - currentIndex]
isLastPass = step == self.log2Size - 1
if isLastPass:
dest = self.resultTexture
index = self.log2Size - step - 1
self.verticalFFT.setShaderInput("source", source)
self.verticalFFT.setShaderInput("dest", dest)
self.verticalFFT.setShaderInput(
"isLastPass", isLastPass)
self.verticalFFT.setShaderInput(
"normalizationFactor", self.normalizationFactor)
self.verticalFFT.setShaderInput(
"butterflyIndex", LVecBase2i(index))
self._queueShader(self.verticalFFT)
currentIndex = 1 - currentIndex
def execute(self):
""" Executes the inverse fft once """
for attr in self.attributes:
self._executeShader(attr)
def _queueShader(self, node):
""" Internal method to fetch the ShaderAttrib of a node and store it
in the update queue """
sattr = node.getAttrib(ShaderAttrib)
self.attributes.append(sattr)
def _executeShader(self, sattr):
""" Internal method to execute a shader by a given ShaderAttrib """
Globals.base.graphicsEngine.dispatch_compute(
(self.size / 16, self.size / 16, 1), sattr,
Globals.base.win.get_gsg())
class WaterManager(DebugObject):
""" Simple wrapper arround WaterDisplacement which combines 3 displacement
maps into one, and also generates a normal map """
def __init__(self):
DebugObject.__init__(self, "WaterManager")
self.options = OceanOptions()
self.options.size = 512
self.options.windDir.normalize()
self.options.waveAmplitude *= 1e-7
self.displacementTex = Texture("Displacement")
self.displacementTex.setup2dTexture(self.options.size,
self.options.size, Texture.TFloat,
Texture.FRgba16)
self.normalTex = Texture("Normal")
self.normalTex.setup2dTexture(self.options.size, self.options.size,
Texture.TFloat, Texture.FRgba16)
self.combineShader = BetterShader.loadCompute(
"Shader/Water/Combine.compute")
self.ptaTime = PTAFloat.emptyArray(1)
# Create a gaussian random texture, as shaders aren't well suited
# for that
setRandomSeed(523)
self.randomStorage = PNMImage(self.options.size, self.options.size, 4)
self.randomStorage.setMaxval((2**16) - 1)
for x in xrange(self.options.size):
for y in xrange(self.options.size):
rand1 = self._getGaussianRandom() / 10.0 + 0.5
rand2 = self._getGaussianRandom() / 10.0 + 0.5
self.randomStorage.setXel(x, y, LVecBase3d(rand1, rand2, 0))
self.randomStorage.setAlpha(x, y, 1.0)
self.randomStorageTex = Texture("RandomStorage")
self.randomStorageTex.load(self.randomStorage)
self.randomStorageTex.setFormat(Texture.FRgba16)
self.randomStorageTex.setMinfilter(Texture.FTNearest)
self.randomStorageTex.setMagfilter(Texture.FTNearest)
# Create the texture wwhere the intial height (H0 + Omega0) is stored.
self.texInitialHeight = Texture("InitialHeight")
self.texInitialHeight.setup2dTexture(self.options.size,
self.options.size, Texture.TFloat,
Texture.FRgba16)
self.texInitialHeight.setMinfilter(Texture.FTNearest)
self.texInitialHeight.setMagfilter(Texture.FTNearest)
# Create the shader which populates the initial height texture
self.shaderInitialHeight = BetterShader.loadCompute(
"Shader/Water/InitialHeight.compute")
self.nodeInitialHeight = NodePath("initialHeight")
self.nodeInitialHeight.setShader(self.shaderInitialHeight)
self.nodeInitialHeight.setShaderInput("dest", self.texInitialHeight)
self.nodeInitialHeight.setShaderInput("N",
LVecBase2i(self.options.size))
self.nodeInitialHeight.setShaderInput("patchLength",
self.options.patchLength)
self.nodeInitialHeight.setShaderInput("windDir", self.options.windDir)
self.nodeInitialHeight.setShaderInput("windSpeed",
self.options.windSpeed)
self.nodeInitialHeight.setShaderInput("waveAmplitude",
self.options.waveAmplitude)
self.nodeInitialHeight.setShaderInput("windDependency",
self.options.windDependency)
self.nodeInitialHeight.setShaderInput("randomTex",
self.randomStorageTex)
self.attrInitialHeight = self.nodeInitialHeight.getAttrib(ShaderAttrib)
self.heightTextures = []
for i in xrange(3):
tex = Texture("Height")
tex.setup2dTexture(self.options.size, self.options.size,
Texture.TFloat, Texture.FRgba16)
tex.setMinfilter(Texture.FTNearest)
tex.setMagfilter(Texture.FTNearest)
tex.setWrapU(Texture.WMClamp)
tex.setWrapV(Texture.WMClamp)
self.heightTextures.append(tex)
# Also create the shader which updates the spectrum
self.shaderUpdate = BetterShader.loadCompute(
"Shader/Water/Update.compute")
self.nodeUpdate = NodePath("update")
self.nodeUpdate.setShader(self.shaderUpdate)
self.nodeUpdate.setShaderInput("outH0x", self.heightTextures[0])
self.nodeUpdate.setShaderInput("outH0y", self.heightTextures[1])
self.nodeUpdate.setShaderInput("outH0z", self.heightTextures[2])
self.nodeUpdate.setShaderInput("initialHeight", self.texInitialHeight)
self.nodeUpdate.setShaderInput("N", LVecBase2i(self.options.size))
self.nodeUpdate.setShaderInput("time", self.ptaTime)
self.attrUpdate = self.nodeUpdate.getAttrib(ShaderAttrib)
# Create 3 FFTs
self.fftX = GPUFFT(self.options.size, self.heightTextures[0],
self.options.normalizationFactor)
self.fftY = GPUFFT(self.options.size, self.heightTextures[1],
self.options.normalizationFactor)
self.fftZ = GPUFFT(self.options.size, self.heightTextures[2],
self.options.normalizationFactor)
self.combineNode = NodePath("Combine")
self.combineNode.setShader(self.combineShader)
self.combineNode.setShaderInput("displacementX",
self.fftX.getResultTexture())
self.combineNode.setShaderInput("displacementY",
self.fftY.getResultTexture())
self.combineNode.setShaderInput("displacementZ",
self.fftZ.getResultTexture())
self.combineNode.setShaderInput("normalDest", self.normalTex)
self.combineNode.setShaderInput("displacementDest",
self.displacementTex)
self.combineNode.setShaderInput("N", LVecBase2i(self.options.size))
self.combineNode.setShaderInput("choppyScale",
self.options.choppyScale)
self.combineNode.setShaderInput("gridLength", self.options.patchLength)
# Store only the shader attrib as this is way faster
self.attrCombine = self.combineNode.getAttrib(ShaderAttrib)
def _getGaussianRandom(self):
""" Returns a gaussian random number """
u1 = generateRandom()
u2 = generateRandom()
if u1 < 1e-6:
u1 = 1e-6
return sqrt(-2 * log(u1)) * cos(2 * pi * u2)
def setup(self):
""" Setups the manager """
Globals.base.graphicsEngine.dispatch_compute(
(self.options.size / 16, self.options.size / 16, 1),
self.attrInitialHeight, Globals.base.win.get_gsg())
def getDisplacementTexture(self):
""" Returns the displacement texture, storing the 3D Displacement in
the RGB channels """
return self.displacementTex
def getNormalTexture(self):
""" Returns the normal texture, storing the normal in world space in
the RGB channels """
return self.normalTex
def update(self):
""" Updates the displacement / normal map """
self.ptaTime[0] = 1 + \
Globals.clock.getFrameTime() * self.options.timeScale
Globals.base.graphicsEngine.dispatch_compute(
(self.options.size / 16, self.options.size / 16, 1),
self.attrUpdate, Globals.base.win.get_gsg())
self.fftX.execute()
self.fftY.execute()
self.fftZ.execute()
# Execute the shader which combines the 3 displacement maps into
# 1 displacement texture and 1 normal texture. We could use dFdx in
# the fragment shader, however that gives no accurate results as
# dFdx returns the same value for a 2x2 pixel block
Globals.base.graphicsEngine.dispatch_compute(
(self.options.size / 16, self.options.size / 16, 1),
self.attrCombine, Globals.base.win.get_gsg())
class WaterManager(DebugObject):
""" Simple wrapper arround WaterDisplacement which combines 3 displacement
maps into one, and also generates a normal map """
def __init__(self):
DebugObject.__init__(self, "WaterManager")
self.options = OceanOptions()
self.options.size = 512
self.options.windDir.normalize()
self.options.waveAmplitude *= 1e-7
self.displacementTex = Texture("Displacement")
self.displacementTex.setup2dTexture(
self.options.size, self.options.size,
Texture.TFloat, Texture.FRgba16)
self.normalTex = Texture("Normal")
self.normalTex.setup2dTexture(
self.options.size, self.options.size,
Texture.TFloat, Texture.FRgba16)
self.combineShader = Shader.loadCompute(Shader.SLGLSL,
"Shader/WaterFFT/Combine.compute")
self.ptaTime = PTAFloat.emptyArray(1)
# Create a gaussian random texture, as shaders aren't well suited
# for that
setRandomSeed(523)
self.randomStorage = PNMImage(self.options.size, self.options.size, 4)
self.randomStorage.setMaxval((2 ** 16) - 1)
for x in xrange(self.options.size):
for y in xrange(self.options.size):
rand1 = self._getGaussianRandom() / 10.0 + 0.5
rand2 = self._getGaussianRandom() / 10.0 + 0.5
self.randomStorage.setXel(x, y, float(rand1), float(rand2), 0)
self.randomStorage.setAlpha(x, y, 1.0)
self.randomStorageTex = Texture("RandomStorage")
self.randomStorageTex.load(self.randomStorage)
self.randomStorageTex.setFormat(Texture.FRgba16)
self.randomStorageTex.setMinfilter(Texture.FTNearest)
self.randomStorageTex.setMagfilter(Texture.FTNearest)
# Create the texture wwhere the intial height (H0 + Omega0) is stored.
self.texInitialHeight = Texture("InitialHeight")
self.texInitialHeight.setup2dTexture(
self.options.size, self.options.size,
Texture.TFloat, Texture.FRgba16)
self.texInitialHeight.setMinfilter(Texture.FTNearest)
self.texInitialHeight.setMagfilter(Texture.FTNearest)
# Create the shader which populates the initial height texture
self.shaderInitialHeight = Shader.loadCompute(Shader.SLGLSL,
"Shader/WaterFFT/InitialHeight.compute")
self.nodeInitialHeight = NodePath("initialHeight")
self.nodeInitialHeight.setShader(self.shaderInitialHeight)
self.nodeInitialHeight.setShaderInput("dest", self.texInitialHeight)
self.nodeInitialHeight.setShaderInput(
"N", LVecBase2i(self.options.size))
self.nodeInitialHeight.setShaderInput(
"patchLength", self.options.patchLength)
self.nodeInitialHeight.setShaderInput("windDir", self.options.windDir)
self.nodeInitialHeight.setShaderInput(
"windSpeed", self.options.windSpeed)
self.nodeInitialHeight.setShaderInput(
"waveAmplitude", self.options.waveAmplitude)
self.nodeInitialHeight.setShaderInput(
"windDependency", self.options.windDependency)
self.nodeInitialHeight.setShaderInput(
"randomTex", self.randomStorageTex)
self.attrInitialHeight = self.nodeInitialHeight.getAttrib(ShaderAttrib)
self.heightTextures = []
for i in xrange(3):
tex = Texture("Height")
tex.setup2dTexture(self.options.size, self.options.size,
Texture.TFloat, Texture.FRgba16)
tex.setMinfilter(Texture.FTNearest)
tex.setMagfilter(Texture.FTNearest)
tex.setWrapU(Texture.WMClamp)
tex.setWrapV(Texture.WMClamp)
self.heightTextures.append(tex)
# Also create the shader which updates the spectrum
self.shaderUpdate = Shader.loadCompute(Shader.SLGLSL,
"Shader/WaterFFT/Update.compute")
self.nodeUpdate = NodePath("update")
self.nodeUpdate.setShader(self.shaderUpdate)
self.nodeUpdate.setShaderInput("outH0x", self.heightTextures[0])
self.nodeUpdate.setShaderInput("outH0y", self.heightTextures[1])
self.nodeUpdate.setShaderInput("outH0z", self.heightTextures[2])
self.nodeUpdate.setShaderInput("initialHeight", self.texInitialHeight)
self.nodeUpdate.setShaderInput("N", LVecBase2i(self.options.size))
self.nodeUpdate.setShaderInput("time", self.ptaTime)
self.attrUpdate = self.nodeUpdate.getAttrib(ShaderAttrib)
# Create 3 FFTs
self.fftX = GPUFFT(self.options.size, self.heightTextures[0],
self.options.normalizationFactor)
self.fftY = GPUFFT(self.options.size, self.heightTextures[1],
self.options.normalizationFactor)
self.fftZ = GPUFFT(self.options.size, self.heightTextures[2],
self.options.normalizationFactor)
self.combineNode = NodePath("Combine")
self.combineNode.setShader(self.combineShader)
self.combineNode.setShaderInput(
"displacementX", self.fftX.getResultTexture())
self.combineNode.setShaderInput(
"displacementY", self.fftY.getResultTexture())
self.combineNode.setShaderInput(
"displacementZ", self.fftZ.getResultTexture())
self.combineNode.setShaderInput("normalDest", self.normalTex)
self.combineNode.setShaderInput(
"displacementDest", self.displacementTex)
self.combineNode.setShaderInput(
"N", LVecBase2i(self.options.size))
self.combineNode.setShaderInput(
"choppyScale", self.options.choppyScale)
self.combineNode.setShaderInput(
"gridLength", self.options.patchLength)
# Store only the shader attrib as this is way faster
self.attrCombine = self.combineNode.getAttrib(ShaderAttrib)
def _getGaussianRandom(self):
""" Returns a gaussian random number """
u1 = generateRandom()
u2 = generateRandom()
if u1 < 1e-6:
u1 = 1e-6
return sqrt(-2 * log(u1)) * cos(2 * pi * u2)
def setup(self):
""" Setups the manager """
Globals.base.graphicsEngine.dispatch_compute(
(self.options.size / 16,
self.options.size / 16, 1), self.attrInitialHeight,
Globals.base.win.get_gsg())
def getDisplacementTexture(self):
""" Returns the displacement texture, storing the 3D Displacement in
the RGB channels """
return self.displacementTex
def getNormalTexture(self):
""" Returns the normal texture, storing the normal in world space in
the RGB channels """
return self.normalTex
def update(self):
""" Updates the displacement / normal map """
self.ptaTime[0] = 1 + \
Globals.clock.getFrameTime() * self.options.timeScale
Globals.base.graphicsEngine.dispatch_compute(
(self.options.size / 16,
self.options.size / 16, 1), self.attrUpdate,
Globals.base.win.get_gsg())
self.fftX.execute()
self.fftY.execute()
self.fftZ.execute()
# Execute the shader which combines the 3 displacement maps into
# 1 displacement texture and 1 normal texture. We could use dFdx in
# the fragment shader, however that gives no accurate results as
# dFdx returns the same value for a 2x2 pixel block
Globals.base.graphicsEngine.dispatch_compute(
(self.options.size / 16,
self.options.size / 16, 1), self.attrCombine,
Globals.base.win.get_gsg())
class WaterManager:
""" Simple wrapper around WaterDisplacement which combines 3 displacement
maps into one, and also generates a normal map """
def __init__(self, water_options):
self.options = water_options
self.options.size = 512
self.options.wind_dir.normalize()
self.options.wave_amplitude *= 1e-7
self.displacement_tex = Texture("Displacement")
self.displacement_tex.setup_2d_texture(
self.options.size, self.options.size,
Texture.TFloat, Texture.FRgba16)
self.normal_tex = Texture("Normal")
self.normal_tex.setup_2d_texture(
self.options.size, self.options.size,
Texture.TFloat, Texture.FRgba16)
self.combine_shader = Shader.load_compute(Shader.SLGLSL,
"/$$rp/rpcore/water/shader/combine.compute")
self.pta_time = PTAFloat.emptyArray(1)
# Create a gaussian random texture, as shaders aren't well suited
# for that
setRandomSeed(523)
self.random_storage = PNMImage(self.options.size, self.options.size, 4)
self.random_storage.setMaxval((2 ** 16) - 1)
for x in range(self.options.size):
for y in range(self.options.size):
rand1 = self._get_gaussian_random() / 10.0 + 0.5
rand2 = self._get_gaussian_random() / 10.0 + 0.5
self.random_storage.setXel(x, y, float(rand1), float(rand2), 0)
self.random_storage.setAlpha(x, y, 1.0)
self.random_storage_tex = Texture("RandomStorage")
self.random_storage_tex.load(self.random_storage)
self.random_storage_tex.set_format(Texture.FRgba16)
self.random_storage_tex.set_minfilter(Texture.FTNearest)
self.random_storage_tex.set_magfilter(Texture.FTNearest)
# Create the texture wwhere the intial height (H0 + Omega0) is stored.
self.tex_initial_height = Texture("InitialHeight")
self.tex_initial_height.setup_2d_texture(
self.options.size, self.options.size,
Texture.TFloat, Texture.FRgba16)
self.tex_initial_height.set_minfilter(Texture.FTNearest)
self.tex_initial_height.set_magfilter(Texture.FTNearest)
# Create the shader which populates the initial height texture
self.shader_initial_height = Shader.load_compute(Shader.SLGLSL,
"/$$rp/rpcore/water/shader/initial_height.compute")
self.node_initial_height = NodePath("initialHeight")
self.node_initial_height.set_shader(self.shader_initial_height)
self.node_initial_height.set_shader_input("dest", self.tex_initial_height)
self.node_initial_height.set_shader_input(
"N", LVecBase2i(self.options.size))
self.node_initial_height.set_shader_input(
"patchLength", self.options.patch_length)
self.node_initial_height.set_shader_input("windDir", self.options.wind_dir)
self.node_initial_height.set_shader_input(
"windSpeed", self.options.wind_speed)
self.node_initial_height.set_shader_input(
"waveAmplitude", self.options.wave_amplitude)
self.node_initial_height.set_shader_input(
"windDependency", self.options.wind_dependency)
self.node_initial_height.set_shader_input(
"randomTex", self.random_storage_tex)
self.attr_initial_height = self.node_initial_height.get_attrib(ShaderAttrib)
self.height_textures = []
for i in range(3):
tex = Texture("Height")
tex.setup_2d_texture(self.options.size, self.options.size,
Texture.TFloat, Texture.FRgba16)
tex.set_minfilter(Texture.FTNearest)
tex.set_magfilter(Texture.FTNearest)
tex.set_wrap_u(Texture.WMClamp)
tex.set_wrap_v(Texture.WMClamp)
self.height_textures.append(tex)
# Also create the shader which updates the spectrum
self.shader_update = Shader.load_compute(Shader.SLGLSL,
"/$$rp/rpcore/water/shader/update.compute")
self.node_update = NodePath("update")
self.node_update.set_shader(self.shader_update)
self.node_update.set_shader_input("outH0x", self.height_textures[0])
self.node_update.set_shader_input("outH0y", self.height_textures[1])
self.node_update.set_shader_input("outH0z", self.height_textures[2])
self.node_update.set_shader_input("initialHeight", self.tex_initial_height)
self.node_update.set_shader_input("N", LVecBase2i(self.options.size))
self.node_update.set_shader_input("time", self.pta_time)
self.attr_update = self.node_update.get_attrib(ShaderAttrib)
# Create 3 FFTs
self.fftX = GPUFFT(self.options.size, self.height_textures[0],
self.options.normalization_factor)
self.fftY = GPUFFT(self.options.size, self.height_textures[1],
self.options.normalization_factor)
self.fftZ = GPUFFT(self.options.size, self.height_textures[2],
self.options.normalization_factor)
self.combine_node = NodePath("Combine")
self.combine_node.set_shader(self.combine_shader)
self.combine_node.set_shader_input(
"displacementX", self.fftX.get_result_texture())
self.combine_node.set_shader_input(
"displacementY", self.fftY.get_result_texture())
self.combine_node.set_shader_input(
"displacementZ", self.fftZ.get_result_texture())
self.combine_node.set_shader_input("normalDest", self.normal_tex)
self.combine_node.set_shader_input(
"displacementDest", self.displacement_tex)
self.combine_node.set_shader_input(
"N", LVecBase2i(self.options.size))
self.combine_node.set_shader_input(
"choppyScale", self.options.choppy_scale)
self.combine_node.set_shader_input(
"gridLength", self.options.patch_length)
# Store only the shader attrib as this is way faster
self.attr_combine = self.combine_node.get_attrib(ShaderAttrib)
def _get_gaussian_random(self):
""" Returns a gaussian random number """
u1 = generateRandom()
u2 = generateRandom()
if u1 < 1e-6:
u1 = 1e-6
return sqrt(-2 * log(u1)) * cos(2 * pi * u2)
def setup(self):
""" Setups the manager """
Globals.base.graphicsEngine.dispatch_compute(
(self.options.size // 16, self.options.size // 16, 1),
self.attr_initial_height,
Globals.base.win.get_gsg())
def get_displacement_texture(self):
""" Returns the displacement texture, storing the 3D Displacement in
the RGB channels """
return self.displacement_tex
def get_normal_texture(self):
""" Returns the normal texture, storing the normal in world space in
the RGB channels """
return self.normal_tex
def update(self):
""" Updates the displacement / normal map """
self.pta_time[0] = 1 + Globals.clock.get_frame_time() * self.options.time_scale
Globals.base.graphicsEngine.dispatch_compute(
(self.options.size // 16, self.options.size // 16, 1),
self.attr_update,
Globals.base.win.get_gsg())
self.fftX.execute()
self.fftY.execute()
self.fftZ.execute()
# Execute the shader which combines the 3 displacement maps into
# 1 displacement texture and 1 normal texture. We could use dFdx in
# the fragment shader, however that gives no accurate results as
# dFdx returns the same value for a 2x2 pixel block
Globals.base.graphicsEngine.dispatch_compute(
(self.options.size // 16, self.options.size // 16, 1),
self.attr_combine,
Globals.base.win.get_gsg())
