Sunday, June 25, 2017


I'm by no means an expert on anything San Diego, having been there only around 1.5 months since leaving Seattle. I did spend 8 years in Seattle though, and here's what I think:

- Seattle is just way too dark of a city for me to live there year round. Here's Seattle vs. San Diego's sunshine (according to

The winter rain didn't bother me much at all. It was the lack of sun. (Hint to Seattle-area corporate recruiters: Fly in candidates from sunnier climates like Dallas to interview during July-August.)

- There's a constant background noise and auditory clutter to Seattle and the surrounding areas that's just getting louder and louder as buildings pop up and people (and their cars) move in.

Eventually this background noise got really annoying. Even downtown San Diego is surprisingly peaceful and quiet by comparison.

- Seattle's density is both a blessing and a curse. It's a very walkable city, so going without a car is possible if you live and work in the right places.

The eastside and westside buses can be incredibly, ridiculously over packed. Seattle needs to seriously get its public transportation act together.

- As a pedestrian, I've found Seattle's drivers to be so much nicer and peaceful on the road vs. San Diego's. CA drivers seem a lot more aggressive.

- San Diego is loaded with amazing beaches. Seattle - not so much.

A few misc. thoughts on Seattle and the eastside tech workers I encountered:

I lived and worked on the eastside (near downtown Bellevue) and westside (U District) for enough time to compare and contrast the two areas. The people in Seattle itself are generally quite friendly and easy going. Things seem to change quickly once you get to the eastside, which feels almost like a different state entirely.

I found eastside people to be much less friendly and living in their own little worlds. I wish I had spent more of my time living in Seattle itself instead of Bellevue. Culturally Bellevue feels cold and very corporate.

The wealthier areas on the eastside seemed the worse. Wealth and rudeness seem highly correlated. So far, I've yet to meet a Bellevue/Redmond tech 10-100 millionaire (or billionaire) that I found to be truly pleasant to be around or work with. I also learned over and over that there is only a weak correlation between someone's wealth and their ability to actually code. In many cases someone's tech wealth seemed to be related to luck of the draw, timing, personality, and even popularity. Some of the wealthiest programmers I met here were surprisingly weak software engineers.

I've seen this happen repeatedly over the years: Average software engineers get showered with mad cash and suddenly they turn inward, become raging narcissistic assholes, and firmly believe they and their code is godly. Money seems to bring out the worse personality traits in people.

Monday, June 19, 2017

Basis's RDO DXTc compression API

This is a work in progress, but here's the API to the new rate distortion optimizing DXTc codec I've been working on for Basis. There's only one function (excluding basis_get_version()): basis_rdo_dxt_encode(). You call it with some encoding parameters and an array of input images (or "slices"), and it gives you back a blob of DXTc blocks which you then feed to any LZ codec like zlib, zstd, LZHAM, Oodle, etc.

The output DXTc blocks are organized in simple raster order, with slice 0's blocks first, then slice 1's, etc. The slices could be mipmap levels, or cubemap faces, etc. For highest compression, it's very important to feed the output blocks to the LZ codec in the order that this function gives them back to you.

On my near-term TODO list is to allow the user to specify custom per-channel weightings, and to add more color distance functions. Right now it supports either uniform weights, or a custom model for sRGB colorspace photos/textures. Also, I may expose optional per-slice weightings (for mipmaps).

I'm shipping the first version (as a Windows DLL) tomorrow.

// File: basis_rdo_dxt_public.h
#pragma once

#include <stdlib.h>
#include <memory.h>

#define BASIS_DLL_EXPORT __declspec(dllexport)  

#if defined(_MSC_VER)
#define BASIS_CDECL __cdecl

namespace basis
   const int BASIS_VERSION = 0x0100;

   typedef unsigned int basis_uint;
   typedef basis_uint rdo_dxt_bool;

   enum rdo_dxt_format
      cRDO_DXT1 = 0,


   const basis_uint RDO_DXT_STRUCT_VERSION = 0xABCD0001;

   const basis_uint RDO_QUALITY_MIN = 1;
   const basis_uint RDO_QUALITY_MAX = 255;

   struct rdo_dxt_params
      basis_uint m_struct_size;
      basis_uint m_struct_version;

      rdo_dxt_format m_format;

      basis_uint m_quality;

      basis_uint m_alpha_component_indices[2];

      basis_uint m_lz_max_match_dist;
      basis_uint m_output_block_size;

      basis_uint m_num_color_endpoint_clusters;
      basis_uint m_num_color_selector_clusters;

      basis_uint m_num_alpha_endpoint_clusters;
      basis_uint m_num_alpha_selector_clusters;

      float m_l;
      float m_selector_rdo_quality_threshold;
      float m_endpoint_selector_rdo_quality_threshold;

      float m_selector_rdo_quality_threshold_low;
      float m_endpoint_selector_rdo_quality_threshold_low;

      float m_block_max_y_std_dev_rdo_quality_scaler;

      basis_uint m_endpoint_refinement_steps;
      basis_uint m_selector_refinement_steps;
      basis_uint m_final_block_refinement_steps;

      float m_adaptive_tile_color_psnr_derating;
      float m_adaptive_tile_alpha_psnr_derating;

      basis_uint m_endpoint_rdo_max_search_distance;

      rdo_dxt_bool m_optimize_final_endpoint_clusters;
      rdo_dxt_bool m_optimize_final_selector_clusters;

      rdo_dxt_bool m_srgb_metrics;
      rdo_dxt_bool m_debugging;
      rdo_dxt_bool m_debug_output;
      rdo_dxt_bool m_hierarchical_mode;
      rdo_dxt_bool m_multithreaded;

   inline void rdo_dxt_params_set_to_defaults(rdo_dxt_params *p)
      memset(p, 0, sizeof(rdo_dxt_params));

      p->m_struct_size = sizeof(rdo_dxt_params);
      p->m_struct_version = RDO_DXT_STRUCT_VERSION;

      p->m_format = cRDO_DXT1;

      p->m_quality = 128;

      p->m_alpha_component_indices[0] = 0;
      p->m_alpha_component_indices[1] = 1;

      p->m_l = .001f;

      p->m_selector_rdo_quality_threshold = 1.75f;
      p->m_endpoint_selector_rdo_quality_threshold = 1.75f;

      p->m_selector_rdo_quality_threshold_low = 1.3f;
      p->m_endpoint_selector_rdo_quality_threshold_low = 1.3f;

      p->m_block_max_y_std_dev_rdo_quality_scaler = 8.0f;

      p->m_lz_max_match_dist = 32768;
      p->m_output_block_size = 8;

      p->m_endpoint_refinement_steps = 2;
      p->m_selector_refinement_steps = 2;
      p->m_final_block_refinement_steps = 1;

      p->m_adaptive_tile_color_psnr_derating = 1.5f;
      p->m_adaptive_tile_alpha_psnr_derating = 1.5f;
      p->m_endpoint_rdo_max_search_distance = 8;

      p->m_optimize_final_endpoint_clusters = true;
      p->m_optimize_final_selector_clusters = true;

      p->m_hierarchical_mode = true;

      p->m_multithreaded = true;

   const basis_uint RDO_DXT_MAX_IMAGE_DIMENSION = 16384;

   struct rdo_dxt_slice_desc
      // Pixel dimensions of this slice. A slice may be a mipmap level, a cubemap face, a video frame, or whatever.
      basis_uint m_image_width;
      basis_uint m_image_height;
      basis_uint m_image_pitch_in_pixels;

      // Pointer to 32-bit raster image. Format in memory: RGBA (R is first byte, A is last)
      const void *m_pImage_pixels;

} // namespace basis

extern "C" BASIS_DLL_EXPORT basis::basis_uint BASIS_CDECL basis_get_version();

extern "C" BASIS_DLL_EXPORT bool BASIS_CDECL basis_rdo_dxt_encode(
   const basis::rdo_dxt_params *pEncoder_params,
   basis::basis_uint total_input_image_slices, const basis::rdo_dxt_slice_desc *pInput_image_slices,
   void *pOutput_blocks, basis::basis_uint output_blocks_size_in_bytes);