hos_BlackBodyRadiation.fuse

--[[
    Black Body Radiation Fuse by Sven Neve / House of Secrets

    Based on the work and code of Hugo Elias et al.
    http://freespace.virgin.net/hugo.elias/models/m_ffire.htm

    This is pretty much a 1 on 1 conversion (with the exception of the gamma correction);
    A lot of this code can be optimized.
    
    
    
    The MIT License (MIT)

    Copyright (c) 2015 Sven Neve

    Permission is hereby granted, free of charge, to any person obtaining a copy
    of this software and associated documentation files (the "Software"), to deal
    in the Software without restriction, including without limitation the rights
    to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
    copies of the Software, and to permit persons to whom the Software is
    furnished to do so, subject to the following conditions:

    The above copyright notice and this permission notice shall be included in all
    copies or substantial portions of the Software.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
    AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
    SOFTWARE.
    
--]]

FuRegisterClass("hos_BlackBodyRadiation", CT_Tool, {
    REGS_Name = "Black Body Radiation",
    REGS_Category = "House of Secrets\\Color",
    REGS_OpIconString = "HBBR",
    REGS_OpDescription = "Black Body Radiation Fuse",
    })


clsource =
[[

float3 Expose(float3 light, float exposure)
{
    return ( 1.0f - exp(light * exposure) );
}
  
kernel void ToolTemplate(   FuReadImage_t inimg,
                            FuWriteImage_t outimg,
                            const int4 datawindow,
                            float mintemp,
                            float maxtemp,
                            float exposure,
                            float gamma)
{
    const int2 ipos = (int2)(get_global_id(1), get_global_id(0)) + datawindow.xy;
    const int2 size = datawindow.zw;
    
    const float h = 6.626f * pow(10.0f, -34.0f);                // Planck's Constant in Js
    const float c = 3.0f * pow(10.0f, 8.0f);                    // Speed Of Light in m/s
    const float k = 1.380f * pow(10.0f, -23.0f);                // Boltzmann Constant in J/K
        
    const float red_wave = 0.7f * pow(10.0f, -6.0f);            // red wavelength in nm
    const float green_wave = 0.56f * pow(10.0f, -6.0f);         // green wavelength in nm
    const float blue_wave = 0.47f * pow(10.0f, -6.0f);          // blue wavelength in nm
    
    float4 img = FuReadImagef(inimg, ipos, size);
    float Y = 0.2126f*img.x + 0.7152f*img.y + 0.0722f*img.z;    // RGB to Relative Luminance
    float T = mix(mintemp, maxtemp, Y);// Temperature in Kelvin
    float3 L = (float3)(red_wave, green_wave, blue_wave);
    L = pow(L, 5.0f) * (exp((h * c)/(k * T * L))*-1.0f);
    L = pow(10.0f,-28.0f) / L;
    
    float3 result = Expose(L, exposure);                        // Clamps values to 1.0, maybe not desirable in Fusion.
    
    // Not sure converting to 2.2 is correct, added it anyway.
    result = pow(result, gamma);// * img.w;

    FuWriteImagef(outimg, ipos, size, (float4)(result, img.w));
}
]]

function Create()
    InImage = self:AddInput("Image", "Image", {
        LINKID_DataType = "Image",
        LINK_Main = 1,
        })
        
    InMinTemp = self:AddInput("Min Temperature", "MinTemperature", {
        LINKID_DataType = "Number",
        INPID_InputControl = "SliderControl",
        INP_Default = 0,
        })
        
    InMaxTemp = self:AddInput("Min Temperature", "MaxTemperature", {
        LINKID_DataType = "Number",
        INPID_InputControl = "SliderControl",
        INP_Default = 5740,
        })
        
    InExposure = self:AddInput("Exposure", "Exposure", {
        LINKID_DataType = "Number",
        INPID_InputControl = "SliderControl",
        INP_Default = 100,
        })
        
    InGamma = self:AddInput("Gamma", "Gamma", {
        LINKID_DataType = "Number",
        INPID_InputControl = "SliderControl",
        INP_Default = 2.2,
        INP_MinAllowed = 0.0000001
        })
        
    OutImage = self:AddOutput("Output", "Output", {
        LINKID_DataType = "Image",
        LINK_Main = 1,
        })                

    mgr = OCLManager()
    if mgr then
        prog = mgr:BuildCachedProgram(self.RegNode, clsource)
    end
end

-- function OnAddToFlow()
    -- mgr = OCLManager()
    -- if mgr then
        -- local path = string.sub(debug.getinfo(1).source, 2)
        -- prog = mgr:BuildCachedProgram("SourceTemplate", path, clsource)
    -- end
-- end

function Process(req) 
    local mintemp = InMinTemp:GetValue(req).Value
    local maxtemp = InMaxTemp:GetValue(req).Value
    local exposure = InExposure:GetValue(req).Value
    local gamma = InGamma:GetValue(req).Value
    local inimg = InImage:GetValue(req)
    local img = Image{ IMG_Like = inimg }
    local out

    if img and prog then
        local incl = prog:CreateImage(inimg, "read")
        local outcl = prog:CreateImage(img, "write")
        if incl and outcl then
            -- create image
            local kernel = prog:CreateKernel("ToolTemplate")

            if kernel then
                prog:SetArg(kernel, 0, incl)
                prog:SetArg(kernel, 1, outcl)
                prog:SetArgInt(kernel, 2, img.DataWindow[1], img.DataWindow[2], img.DataWindow[3] - img.DataWindow[1], img.DataWindow[4] - img.DataWindow[2])
                prog:SetArg(kernel, 3, mintemp)
                prog:SetArg(kernel, 4, maxtemp)
                prog:SetArg(kernel, 5, exposure)
                prog:SetArg(kernel, 6, 1/gamma)
                --prog:SetWorkgroupSize(64) // No idea what the beef with Nvidia OpenCL is, but workgroups and sizes always blow up when i use 'm.

                prog:RunKernel(kernel)
                if self.Status then
                    prog:Download(outcl, img)
                    out = img
                end
            end
        end
        if incl then
            incl:ReleaseCLObject()
        end
        if outcl then
            outcl:ReleaseCLObject()
        end
    end
    
    -- if prog and not success then        -- failed? may need to build a new context
        -- prog = nil
        -- mgr = nil
        -- collectgarbage()                -- force cleanup now

        -- mgr = OCLManager()
        -- if mgr then
            -- -- local path = string.sub(debug.getinfo(1).source, 2)
            -- -- prog = mgr:BuildCachedProgram("Fuse.OpenCLSample", path, clsource)
            --prog = mgr:BuildCachedProgram(self.RegNode, clsource)
        -- end
    -- end
    
    
    -- local te = TimeExtent()
    -- if seetherate > 0.0 then
        -- te = TimeExtent(req.Time, req.Time, TIME_UNDEFINED)
    -- end

    -- req:SetOutputData(OutImage, out, te)
    
    OutImage:Set(req, out)
end