// Because file only specifies a number of control points, a full color table must be made from these control points by linearly interpolating
void TransferFunction::LoadLookup(std::vector<glm::vec4> &colorTable)
{
glm::vec4 previousColor(0.0f);
float previousIntensity = 0.0f;
int next = 0;
for (int i=0; i<256; i++)
{
float currentIntensity = (float)i / (float)255;
while (next < numIntensities && currentIntensity > intensities[next])
{
previousIntensity = intensities[next];
previousColor = colors[next];
next++;
}
if (next < numIntensities)
colorTable[i] = LERPColor(previousColor, colors[next], previousIntensity, intensities[next], currentIntensity);
else
colorTable[i] = LERPColor(previousColor, glm::vec4(0.0f), previousIntensity, 1.0f, currentIntensity);
}
CopyToTex(colorTable);
}
void TransferFunction::loadLookup()
{
glm::vec4 previousColor(0.0f);
float previousIntensity = 0.0f;
int next = 0;
for (int i=0; i<TRANSFER_FN_TABLE_SIZE; i++)
{
float currentIntensity = (float)i / (float)255;
while (next < m_numIntensities && currentIntensity > m_intensities[next])
{
previousIntensity = m_intensities[next];
previousColor = m_colors[next];
next++;
}
if (next < m_numIntensities)
m_colorTable[i] = LERPColor(previousColor, m_colors[next], previousIntensity, m_intensities[next], currentIntensity);
else
m_colorTable[i] = LERPColor(previousColor, glm::vec4(0.0f), previousIntensity, 1.0f, currentIntensity);
}
}
