T:/Eigene Dateien/Visual Studio 2008/Projects/VisLuFramework/src/ColourPicker.cpp

#include "ColourPicker.h"

#include "TransferFunctionGUI.h"


GLuint ColourPicker::colourPickerTextureID = -1;
float ColourPicker::colourPickerSliderValue = 0.f;
int ColourPicker::colourPickerOffsetX = 10;

ColourPickerSliderMode ColourPicker::g_iColourPickerLabSwitchMode = ColourPickerSliderMode_L;

int ColourPicker::colourPickerHeight = 180 + TransferFunctionGUI::g_iTransferFunctionTextureDisplayHeight + TransferFunctionGUI::g_iTransferFunctionTextureDisplayYOffset;
int ColourPicker::colourPickerWidth = colourPickerHeight;

RGBA_Colour* ColourPicker::colourPickerTextureData = new RGBA_Colour[colourPickerWidth * colourPickerHeight];



Lab_Colour ColourPicker::getColourPickerPositionColour(float x, float y)
{
        float L = 0.f;
        float a = 0.f;
        float b = 0.f;

        if(g_iColourPickerLabSwitchMode != ColourPickerSliderMode_L)
        {
                L = 100.f * y / (float)colourPickerHeight;
                if(g_iColourPickerLabSwitchMode != ColourPickerSliderMode_A)
                {
                        b = colourPickerSliderValue;
                        a = 130.f - 260.f * x /(float)colourPickerHeight;
                }
                else
                {
                        a = colourPickerSliderValue;
                        b = 130.f - 260.f * x /(float)colourPickerHeight;
                }
        }
        else
        {
                L = colourPickerSliderValue;
                a = 130.f - 260.f * x /(float) colourPickerWidth;
                b = 130.f - 260.f * y /(float)colourPickerHeight;
        }

        return Lab_Colour(L, a, b);
}

void ColourPicker::initColourPickerTexture()
{
        glGenTextures(1, &colourPickerTextureID);

        get_errors();

        if(colourPickerTextureID != GLuint(-1))
        {
                get_errors();
                glBindTexture(GL_TEXTURE_2D, colourPickerTextureID);

                glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S, GL_CLAMP);
                glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_T, GL_CLAMP);

                glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
                glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);

                glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, colourPickerWidth, colourPickerHeight, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);

                get_errors();
        }

        refreshColourPickerTexture(glutGetWindow());
}



void ColourPicker::refreshColourPickerTexture(int windowID)
{
        glutSetWindow(windowID);

        for(int y = 0; y < colourPickerHeight; ++y)
        {
                for(int x = 0; x < colourPickerWidth; ++x)
                {
                        int i = colourPickerWidth * y + x;

                        Lab_Colour colour = getColourPickerPositionColour((float)x, (float)y);

                        colourPickerTextureData[i] = RGBA_Colour(toRGB(colour), GLubyte(255));
                }
        }
        if(colourPickerTextureID != GLuint(-1))
        {
                glBindTexture(GL_TEXTURE_2D, colourPickerTextureID);
                glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, colourPickerWidth, colourPickerHeight, GL_RGBA, GL_UNSIGNED_BYTE, colourPickerTextureData);
                get_errors();
        }

}