Another update as I am getting into the nitty-gritty detail of the trade system now.
As I mentioned earlier, the existing convoy system and the concept of Trade Routes have been removed. The spaceports that were used to generate the trade points for the convoys have been replaced with a Commercial Spaceport, which is 1200 BP instead of 4800. The only function of this facility is to speed up loading and unloading. Additional levels speed it up further. The actual modifier is the normal loading time divided by (spaceport level +1). So a planet with a level 2 Commercial Spaceport will be able to load cargo three times as fast as a colony with no spaceport.
The cargo sizes and the actual income rates for the trades have been setup. Each Trade Good requires 2500 cargo points, or half a cargo hold. Thus a regular freighter with five cargo holds can carry ten trade goods. This matches the size of infrastructure, which makes things easier. Every time a freighter picks up trade goods, the parent government receives 0.5 wealth per Trade Good in tax from the planet-based manufacturer, or 5 wealth for an average consignment. When the freighter arrives, the parent government receives 0.5 wealth per Trade Good in tax on the profit of the Shipping Line. The reason this is split is because while a trade conducted entirely within an Empire will yield 1 wealth per trade good, the goods might be carried by a foreign-flagged vessel, in which case you only get the export taxes, or it might be a consignment carried by one of your shipping lines from one foreign pop to another, in which case you only get the shipping taxes. Shipping from your Empire to another will provide export taxes but imports from a foreign power will yield nothing, unless they are carried in a freighter owned by a Shipping Line of your race, in which case you get the shipping taxes. This is worked out automatically and you see the different tax types in the Empire income breakdown. This is all up and working already.
The Shipping Line itself receives 2 wealth for each successfully delivered trade good (20 for a normal run), regardless of the nationality of the start and destination pops. The shipping line will use this income to eventually buy additional ships. A new shipping Line window has been added that allows you to see the Shipping Lines, along with the number of ships they own, their total tonnage, their income over the last twelve months, their current wealth and their total assets. A list of their ships is provided, along with tonnage, current location, destination and cargo. Also, a list of recent deliveries is shown to demonstrate where they are operating.
The existing Trade Point Creation tech line will be replaced with some type of Increased Civilian Trade tech line. This will boost both the demand and production of trade goods. So with a twenty percent increase, pops will demand goods equal to 120% of the population and all trade good production will increase by 20%. This will increase the amount of trading opportunities and generate more revenue for the shipping companies and the government.
The above has been implemented in a fairly similar way to that described in my original mail but I have also integrated it with wealth production to create a more realistic whole.
The Wealth Rate and Trading Rate tech lines have both been replaced with a tech named "Expand Civilian Economy by 20%". Researching this tech will increase the income of all populations by twenty percent and will increase the production and demand of all trade goods within your Empire by twenty percent. This is also the first example of what I am calling Replicating Techs. When you research this for the first time (at a cost of 2500 RP), the program creates a race-specific version of the tech. Every time you research it, the tech remains the same but the research cost doubles. This means only one line per race on the tech system tables for this tech and it also means that a situation can be created where different races pay different amounts for the same level of per capita income, which should finally solve what I have come to think of as the "China Problem"
The "China Problem" is that China has a population five times greater than the United States but a much lower per-capita income. This is hard to simulate in Aurora because income is based directly on population so, all things being equal, two equal size pops will generate the same income. I have tried to fudge this by adding lower and expensive tech levels for wealth to give a China-type power some hurdles to overcome before catching up. However, once it gets on the bottom rung of the 'normal' wealth tech line, it can catch up fairly quickly. Besides, this is obviously a fudge and the realism aspect is hard to accept, especially when it suddenly becomes cheaper to increase wealth at 20 per million pop.
The new Replicating Tech allows a much neater approach. When a race is manually generated you are informed that a regular TN race will receive 100% of normal income and you are asked if you want to modify this percentage. Lets assume you do and you decided to give China 15% of normal income. Normal Income is 20 wealth per million pop so China will start with 3 wealth per million pop. However, as the tech system is now entirely percentage based and specific to each race, it doesn't matter what the starting point is. It will cost the US 2500 RP to move from 20 wealth to 24 wealth and 5000 RP to move to 28.8 wealth. It will cost China 2500 RP to move from 3 wealth to 3.6 wealth and 5000 RP to move to 4.32 wealth, etc. Now it could be argued that China will improve its economy to be more efficient and this low start will penalise them. However, the US could also improve its economy and stay ahead. All this is doing is reflecting the start point for both nations. When I finally get around to sorting out real government modifiers, this will also be very useful in simulating the econmic starting point for different government types.
The per capita income figure shown on the Trade tab of the Pop window will now have real relevance and will be the wealth per million figure
Steve