In the shop windows there were Christmas trees and silver tinsel and red balls galore in a brave effort for the festive season. But a different spirit ruled on the streets of this port city last Friday: the spirit of the ubiquitous anti-riot police, the ZOMOs. Patrolling in groups of three or six or more and wearing helmets and visors, the ZOMOs took over for regular police in a saturation ''security'' exercise Dec. 16. That was the day Gdansk mourned its victims in the food riots of December 1970.
It was an incongruous, distasteful spectacle and, it turned out, unnecessary. The day passed without incident, apart from a small crowd calling out Solidarity slogans outside the church where a mass was said in the evening.
Maybe, at -10 degrees C. (14 degrees F.), it was too cold. But the more likely explanation is that people are too tired from day-to-day troubles and have become apathetic about the whole situation.
It was another massive use of police manpower - and political overkill - that has characterized previous Solidarity anniversaries. The authorities would say that putting the security forces on the streets en masse, not only here but also in other former Solidarity strongholds, had achieved its objective. They see the small turnout as a failure for the remnants of the underground, which had called for a day of protest.
But in terms of public relations and the government's attempt to win some popular support and cooperation, this repeated use of the ZOMO ''deterrent'' surely has had quite the opposite effect.
For example, it was instructive to see how people, despite being stopped, checked, and then kept from going by or near the monument, contrived a disdainful aloofness and a studied indifference to the pestering of the drab-uniformed presence around them.
Dec. 16 suggested, in fact, that support for the militant underground by now has probably fizzled out. On the eve of the anniversary, a minor demonstration erupted in Wroclaw, but the day itself was quiet everywhere. That may be some sort of gain for the government, but not in its bid for public confidence.
Gdansk, of course, is a special case. It is the home of the union movement that started along the Baltic in the late 1970s and the mass labor organization that in 1980 took over the whole country. That is why it always seems so much sadder here.
Today Poland's continuing economic depression also seems worse here.
Lech Walesa's shipyard itself is undergoing a depression. The boom and full order books of the 1970s are things of the past. The yard's party organization was told earlier this month that production had fallen off 25 percent and that exports had also declined.
In 1982, only 60 percent of Poland's technical capacity was used. In the first half of this year, sales of products and services were up 30 percent over the same period in 1982, but overall production had dropped 12 percent.
In these crisis years, shortages and bottlenecks of steel and other materials have been partly to blame. But talks with workers in the yard show to what an extent the working tempo was - and still is - affected by the crackdown against Solidarity.
The party claims 2,000 members among the yard's work force of 13,000 to 14, 000. More significant, however, is how few workers have joined the new unions set up by the government in Solidarity's place. They claim only about one worker in six throughout the country.
There have been modest upturns in some sectors of Polish industry, some modest improvements in consumer stores. After fears to the contrary, the government has just said the meat ration (21/2 kilograms, or 5.5 pounds, per person) will be maintained next year after all. But for most Poles, more than half of the ration will still be less expensive, poorer quality meat like sausage.
Several large shipments of Cuban oranges and lemons have reportedly arrived here. But none was visible in Gdansk shops this weekend - nor, for that matter, in Warsaw. It is said, however, that consignments were being sent directly to places of work to ensure fair distribution.
It is the same with tea, which lately has been in even shorter supply in the shops than coffee. One explanation is that because of a shortage of tea packaging materials it was being sent to factories and other big employment centers in bulk for distribution.
There is some modicum of Christmas fare on the markets, but the best is at ''free-market,'' i.e., high, prices. Supplies seem stabilized enough to suggest there will not be hunger in the stricter sense of the word this winter. Average monthly pay is reportedly up to 14,000 zlotys (about $150).
But most Poles are living a day-to-day, hand-to-mouth existence, with up to 60 percent of medium and lower wages absorbed by food costs.
About 20 percent of Polish families or individuals who live on 5,000 or fewer zlotys per capita each month need additional state and charity aids outside the living-index benefits.