Function d3d_SetGammaValue

legacy/renderer/Direct3D.cpp:2990–3017

Sets the gamma correction value

// Sets the gamma correction value
void d3d_SetGammaValue(float val) {
  D3D_preferred_state.gamma = val;

  if (!d3d_CanGamma)
    return;

  mprintf(0, "Setting gamma to %f\n", val);

  DDGAMMARAMP rampvals;

  for (int i = 0; i < 256; i++) {
    float norm = (float)i / 255.0;

    float newval = powf(norm, 1.0f / val);

    newval *= 65535;

    newval = std::min(65535, newval);
    newval = std::max(0, newval);

    rampvals.red[i] = newval;
    rampvals.green[i] = newval;
    rampvals.blue[i] = newval;
  }

  HRESULT rval = lpGammaControl->SetGammaRamp(0, &rampvals);
  mprintf(0, "Gamma return val is %d (%x) (%s)\n", rval, rval, d3d_ErrorString(rval));
}

// Gets the current state of the renderer
void d3d_GetRenderState(rendering_state *rstate) { memcpy(rstate, &D3D_state, sizeof(rendering_state)); }