Protoss
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nexus: When a probe is being produced a light will shoot up the horse shoe shape on the front of the structure.
When a mother ship is being produced a column of light will shoot from the sky to the top of the building.
Gateway: when a unit is being made two arms come out of the building, the crystal in the middle turns into a light that shines to the top of the building. When the gateway warps into a warpgate the top of the building folds down slowly and the crystal that was once in the middle turns into a ball of energy.
Warpgate: A light flies out of the top of the structure when a unit is warped in somewere else on the map.
Forge: There are some "blades" near the rear that begin to spin while an upgrade is being researched. Also a ball of light appears on the side while the front of the building folds up to reveal a spinning light.
Cybernetics Core: The middle of the building starts to spin, and the dials on the side twitch faster. The center and the dials also start to glow red.
Assimilator: The front of the assimilator pumps slightly when probes are mining from it. When the geyser is out of gas the assimilator will turn red. A red light crystal will also appear near the middle of the structure.
Robotics Facility: When producing a unit the building rears up and creates a large hologram in in the middle of the building.
Stargate: When the building is producing a unit the sides swell outward. A hologram also appears in the middle of the building depicting the unit that is being warped in. (If a void wray is being warped in you will see a void wray, if a phoenix is being warped you will see a phoenix ect.)
Fleet beacon: The large globe in the middle will glow brightly when upgrading.
Twilight Council: The three post in the middle of the building will move outward ever so slightly while upgrading. also the lights on the posts will start to shoot faster.
Templar Archives: When upgrading the middle of the building will raise up and glow red, while a white light blinks underneath the section.
Robotics Bay: When upgrading the arms on the outside will begin to move wildly while a bright light appears in the center.
A swirling blur will appear on a building that is being crono boosted by the nexus.
When a Protoss building becomes damaged electricity spurts out around the edges of the protoss building.
If a Protoss building still has shield it can be seen while being attacked.
Un-powered Protoss buildings lose their shinny gold paint job and trade it in for a dull brown. All animation on the building stops. Here is an un-powered gateway next to a shinny nexus.
This Tip is from mlgbx.
On the lowest "Shadows" setting, you can distinguish between similarly-sized Protoss buildings as they are warping in without clicking on them. Gateways do not have a shadow under the warp-in animation, but Stargates do. Dark Shrines do not have shadows, but Pylons do. There are also small differences in the heights of hit point bars: Stargate bars are higher than Gateway bars, and Dark Shrine bars are higher than Pylon bars.
dark shrine v pylon
Gateway right stargate left
When a mother ship is being produced a column of light will shoot from the sky to the top of the building.
Gateway: when a unit is being made two arms come out of the building, the crystal in the middle turns into a light that shines to the top of the building. When the gateway warps into a warpgate the top of the building folds down slowly and the crystal that was once in the middle turns into a ball of energy.
Warpgate: A light flies out of the top of the structure when a unit is warped in somewere else on the map.
Forge: There are some "blades" near the rear that begin to spin while an upgrade is being researched. Also a ball of light appears on the side while the front of the building folds up to reveal a spinning light.
Cybernetics Core: The middle of the building starts to spin, and the dials on the side twitch faster. The center and the dials also start to glow red.
Assimilator: The front of the assimilator pumps slightly when probes are mining from it. When the geyser is out of gas the assimilator will turn red. A red light crystal will also appear near the middle of the structure.
Robotics Facility: When producing a unit the building rears up and creates a large hologram in in the middle of the building.
Stargate: When the building is producing a unit the sides swell outward. A hologram also appears in the middle of the building depicting the unit that is being warped in. (If a void wray is being warped in you will see a void wray, if a phoenix is being warped you will see a phoenix ect.)
Fleet beacon: The large globe in the middle will glow brightly when upgrading.
Twilight Council: The three post in the middle of the building will move outward ever so slightly while upgrading. also the lights on the posts will start to shoot faster.
Templar Archives: When upgrading the middle of the building will raise up and glow red, while a white light blinks underneath the section.
Robotics Bay: When upgrading the arms on the outside will begin to move wildly while a bright light appears in the center.
A swirling blur will appear on a building that is being crono boosted by the nexus.
When a Protoss building becomes damaged electricity spurts out around the edges of the protoss building.
If a Protoss building still has shield it can be seen while being attacked.
Un-powered Protoss buildings lose their shinny gold paint job and trade it in for a dull brown. All animation on the building stops. Here is an un-powered gateway next to a shinny nexus.
This Tip is from mlgbx.
On the lowest "Shadows" setting, you can distinguish between similarly-sized Protoss buildings as they are warping in without clicking on them. Gateways do not have a shadow under the warp-in animation, but Stargates do. Dark Shrines do not have shadows, but Pylons do. There are also small differences in the heights of hit point bars: Stargate bars are higher than Gateway bars, and Dark Shrine bars are higher than Pylon bars.
dark shrine v pylon
Gateway right stargate left
Terran
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Command Center: When making an scv, lights in the main door will turn on and off while welding sparks shoot out of the door. Smaller lights on the top and side of the Command Center will begin to pulsate. This graphic remains the same whether the Command Center has been turned into an Orbital command or a Planetary fortress.
When the Command Center is being morphed into a Planetary fortress or Orbital Command, you can tell, by the graphic which one it will be before the morphing is complete.
Barracks: When making units lights on the sides of the barrack begin to flicker, while steam emits from the top vent.
Engineering Bay: The pistons on the side will start to pump, while lights flash when upgrades are being researched.
Bunker: When a bunker is occupied by one or more units the top of the bunker will sink down and a light will turn on inside. The door at the front of the bunker also closes.
Reactor: The graphic is the same no matter witch building it is attached to. When a unit is being produced (even if only one unit is being produced from the building) the reactor will glow bright green, while the center spins. Small clamp looking devices on the sides will also start to slightly go in and out.
Tech Lab: When in use the front fan will begin to spin and the rear piston will go out, becoming surrounded by a ball of green energy. The tech lab only becomes animated when an upgrade is being researched, and not when a unit is being produced.
When Tech labs and reactors are approximately 80% complete it can be told witch one it will be once construction is complete.
Factory: When units are in production, welding sparks will begin to shoot out of the front door, while lights turn on in off inside the door and on the out side of the building. The building begins to "bounce." The satellite will start to move back and forth, pistons on the roof will pump, and steam will come out of the side vent.
Starport: When units are being created the structure will start slightly bouncing, the center landing zone will lower as sparks fly and lights flash from the landing area.
Armoury: When the building is researching upgrades the circle in the center of the structure will start to spin rapidly.
Refinery: When scvs are mining from a refinery arms on the sides of the building will begin to take cans out of the geyser. When the geyser is out of gas the refinery will turn bright red and a red strobe light will start going off.
Ghost Academy: When a nuke is being made or an upgrade is being researched a bright red column of light will shine from the sky down into the middle of the building. The buildings animation will greatly quicken, and lights will flash all over the building. From what i can tell, it can not be told weather a nuke is being stored in the silo or not, but it can be seen being launched.
Fusion core: When upgrading the fusion cores cylinders will start moving up and down, while the center of the building raises up.
Supply Depots: Supply depots obviously have different graphics when raised, lowered and, supply dropped.
Terran buildings smoke when damaged to yellow and burn when near the bottom of yellow and in red.
When the Command Center is being morphed into a Planetary fortress or Orbital Command, you can tell, by the graphic which one it will be before the morphing is complete.
Barracks: When making units lights on the sides of the barrack begin to flicker, while steam emits from the top vent.
Engineering Bay: The pistons on the side will start to pump, while lights flash when upgrades are being researched.
Bunker: When a bunker is occupied by one or more units the top of the bunker will sink down and a light will turn on inside. The door at the front of the bunker also closes.
Reactor: The graphic is the same no matter witch building it is attached to. When a unit is being produced (even if only one unit is being produced from the building) the reactor will glow bright green, while the center spins. Small clamp looking devices on the sides will also start to slightly go in and out.
Tech Lab: When in use the front fan will begin to spin and the rear piston will go out, becoming surrounded by a ball of green energy. The tech lab only becomes animated when an upgrade is being researched, and not when a unit is being produced.
When Tech labs and reactors are approximately 80% complete it can be told witch one it will be once construction is complete.
Factory: When units are in production, welding sparks will begin to shoot out of the front door, while lights turn on in off inside the door and on the out side of the building. The building begins to "bounce." The satellite will start to move back and forth, pistons on the roof will pump, and steam will come out of the side vent.
Starport: When units are being created the structure will start slightly bouncing, the center landing zone will lower as sparks fly and lights flash from the landing area.
Armoury: When the building is researching upgrades the circle in the center of the structure will start to spin rapidly.
Refinery: When scvs are mining from a refinery arms on the sides of the building will begin to take cans out of the geyser. When the geyser is out of gas the refinery will turn bright red and a red strobe light will start going off.
Ghost Academy: When a nuke is being made or an upgrade is being researched a bright red column of light will shine from the sky down into the middle of the building. The buildings animation will greatly quicken, and lights will flash all over the building. From what i can tell, it can not be told weather a nuke is being stored in the silo or not, but it can be seen being launched.
Fusion core: When upgrading the fusion cores cylinders will start moving up and down, while the center of the building raises up.
Supply Depots: Supply depots obviously have different graphics when raised, lowered and, supply dropped.
Terran buildings smoke when damaged to yellow and burn when near the bottom of yellow and in red.
Zerg
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With Zerg it is a little harder to tell especially with certain buildings. For the most part the swaying and breathing of the living Zerg building will quicken when something is going on.
Hatchery: When an upgrade is taken place the five claws at the top of the building move faster. (This goes for the lair and the hive too, all three structures have those five claws) the upgrade graphic is the same for when a queen is being produced. When a unit is being made an egg can be seen at the base of the building next to the larvae.
When the queen has injected the building four large green balls appear on the structure.
The Hatchery and lair also get covered with tissue and beats rapidly when morphing up to the next tier.
Spawning Pool: The breathing of the building quickens while the water in the pool trembles more violently, when upgrading.
Evolution Chamber: Animation slightly quickens, appears to slightly "jiggle." (most noticeably around the pink spiked area.)
Roach Warren: When upgrading the speed of animation quickens, while a small roach pops his head in and out of the tunnel opening.
Hydralisk Den: When the Hrydra Den is researching the tube that runs down the middle starts to buck while the mouth proceeds to chomp.
Infestation Pit: When researching the animation will speed up while the center "mouth" glows red.
Baneling Nest: The building will straighten up when upgrading. The "legs" of the building will also start to twitch and fidget.
Extractor: The extractor will turn bright red once all gas is mined from the geyser.
Spire: The Spire appears to bob up and down once upgrades have started. The top of the spire will start to pulsate six bright red dots from underneath the skin.
The Spire winds down while it morphs into a Greater Spire.
Greater Spire: The Greater Spire appears to "breath" harder when researching upgrade. It also becomes brightly flushed underneath its horns.
Ultralisk Cavern: When upgrading the Ultralisk Cavern's green sacks begins to pump as it's side claws twitch quickly. The little mouth in the center of the building also begins to chomp open and shut.
Creep Tumors: Creep tumors lose their pink spot after they are used. They are replaced by small eyes that open from time to time.
Contaminated Buildings: When contaminated a building becomes covered in crusty goo.
Zerg buildings bleed when they are damaged, the more they are hurt the more they bleed.
Hatchery: When an upgrade is taken place the five claws at the top of the building move faster. (This goes for the lair and the hive too, all three structures have those five claws) the upgrade graphic is the same for when a queen is being produced. When a unit is being made an egg can be seen at the base of the building next to the larvae.
When the queen has injected the building four large green balls appear on the structure.
The Hatchery and lair also get covered with tissue and beats rapidly when morphing up to the next tier.
Spawning Pool: The breathing of the building quickens while the water in the pool trembles more violently, when upgrading.
Evolution Chamber: Animation slightly quickens, appears to slightly "jiggle." (most noticeably around the pink spiked area.)
Roach Warren: When upgrading the speed of animation quickens, while a small roach pops his head in and out of the tunnel opening.
Hydralisk Den: When the Hrydra Den is researching the tube that runs down the middle starts to buck while the mouth proceeds to chomp.
Infestation Pit: When researching the animation will speed up while the center "mouth" glows red.
Baneling Nest: The building will straighten up when upgrading. The "legs" of the building will also start to twitch and fidget.
Extractor: The extractor will turn bright red once all gas is mined from the geyser.
Spire: The Spire appears to bob up and down once upgrades have started. The top of the spire will start to pulsate six bright red dots from underneath the skin.
The Spire winds down while it morphs into a Greater Spire.
Greater Spire: The Greater Spire appears to "breath" harder when researching upgrade. It also becomes brightly flushed underneath its horns.
Ultralisk Cavern: When upgrading the Ultralisk Cavern's green sacks begins to pump as it's side claws twitch quickly. The little mouth in the center of the building also begins to chomp open and shut.
Creep Tumors: Creep tumors lose their pink spot after they are used. They are replaced by small eyes that open from time to time.
Contaminated Buildings: When contaminated a building becomes covered in crusty goo.
Zerg buildings bleed when they are damaged, the more they are hurt the more they bleed.