Simon seems to be practical in his opinion about Piggy and sees him as an outsider doing what he can to help support the group.
Jack in general sees piggy as a fat coward that does little in the way of helping the tribe. Jack's judgement of the law law and politics, Piggy tries to provide, is useless since it provides no tangible protection or food. His vision of Piggy deteriorates along with his hunters opinions to the point where Piggy is no longer considered human.
Ralph's opinion of Piggy is more complicated. Like Jack, Ralph's initial view of Piggy is that he is someone to be made fun of; however, throughout the course of the story, Ralph becomes more and more protective of Piggy. Since Piggy represents civilization, which Jack desires, his parenting of Piggy is expected. For good reason, Ralph mourns Piggy as his last thought in the book. With Piggy's death, the boys lose their last aspect of civilization and become savages- Something Ralph realizes they can never get back.
The quotes are from my collector's edition- I kept them in order in case your page numbering is different.
The opinions of piggy are mixed within the group. Even Ralph, who is Piggy's most staunch ally wavers over backing the boy. Piggy is naive and does not fully understand the interactions of his peers. He for example believes that the conch is the fulcrum of power and not the fire. This is because he believes that they can build a society where he is considered not only an equal but also an authority. In many ways Piggy represents civilization in the group. His ideas of law and order are used by the group but eventually fall to the wayside and are eventually lost as is Piggy.
Ralph's first interaction with Piggy is very telling about Piggy and Ralph himself. It is obvious in this interaction that Piggy is socially awkward. He makes only one request of Ralph:
“I don’t care what they call me,” he said confidentially, “so long as they don’t call me what they used to call me at school.”
Likewise in page 14 and 15 Ralph responds to Piggy's pleas about his various concerns about swimming by saying "Sucks to your auntie!" and "Sucks to your ass-mar!" in turn.
Ralph, however, does come to accept Piggy and stands up for him when the boys meet for the first time. (In his way.)
Jack's initial disdain for Piggy due to his weight is evident and Ralph's unintentionally betrayal stings. Piggy shows this by being reluctant to vote for Ralph for chief of the island.
Most of Jack's comments are generally full of disdain:
“You’re always scared. Yah–Fatty!” pg 62-
“Who cares what you believe—Fatty!” pg 127
“You shut up, you fat slug!” pg 129
And Jack isolates Piggy from almost the beginning of the boy’s interaction with one another. This puts Ralph in an interesting position- At first he follows Jack’s lead: pg 31
Simon’s effort to support Piggy is generally ignored by everyone including Piggy: pg. 58
Ralph’s personal feelings about Piggy are revealed on page: 91-
Ralph turned and smiled involuntarily. Piggy was a bore; his fat, his ass-mar and his matter-of-fact ideas were dull, but there was always a little pleasure to be got out of pulling his leg, even if one did it by accident.
During the confrontation between the groups of boys over the fire going out during their chance at rescue, Jack, Simon, and Ralph’s actions are very telling regarding their attitudes toward Piggy: pg 100
Jack intentionally make’s Piggy an outsider later on in the chapter when they are dividing the meat from the pig. Pg 103 Again it is Simon who comes to Piggy’s aide.
Jack and Ralph's discussion regarding hunting the beast also brings up their views on Piggy: pg 144
“There was no need! Now there is. Piggy’ll look after them.”
“That’s right. Keep Piggy out of danger.”
“Have some sense. What can Piggy do with only one eye?”
The rest of the boys were looking from Jack to Ralph, curiously.
Jack is irritated with Ralph for protecting Piggy. However even Ralph takes note that Piggy is not a whole character now that his glasses are broken. This gives a sense that Ralph views Piggy as somewhat of a burden. Jack continues to comment that Piggy is not equal to the other leaders: Pg 145
Jack broke in, contemptuously.
“You’re always scared.”
“I got the conch—”
“Conch! Conch!” shouted Jack. “We don’t need the conch any more.
We know who ought to say things. What good did Simon do speaking, or Bill, or Walter? It’s time some people knew they’ve got to keep quiet and leave deciding things to the rest of us.”
Jack's contempt for Piggy increases to make Piggy represent being a coward. As Jack begins to fight for power he uses Piggy as an interchangeable word for Coward. pg 181
As Ralph begins to adjust to the unraveling of the island’s politics, he becomes closer to Piggy:
After Simon’s death, Ralph draws closer to Piggy marveling in his innocence. Pg 225
It is at this moment Piggy becomes more than a confidant to Ralph. Piggy allows him to excuse himself from the murder: pg. 226
Ralph’s personal protection of Piggy continues through the story. Pg. 252
is first words were a gasp, but audible.
“—calling an assembly.”
The savages guarding the neck muttered among themselves but made no motion. Ralph walked forwards a couple of steps. A voice whispered urgently behind him.
“Don’t leave me, Ralph.”
“You kneel down,” said Ralph sideways, “and wait till I come back.”
And again on pg 255-
“Listen. We’ve come to say this. First you’ve got to give back Piggy’s specs. If he hasn’t got them he can’t see. You aren’t playing the game—”
Roger’s vision of Ralph and Piggy while he is leaning on the rock, is very telling that Piggy has lost his human identity as far as the hunters are concerned:
Pg 259: “Below him, Ralph was a shock of hair and Piggy a bag of fat.”
Jack’s reaction to Piggy’s death is one of disassociation. Rather than remarking on the rather gruesome death of the boy, Jack focuses his attention on the destruction of the Conch.
Suddenly Jack bounded out from the tribe and began screaming wildly.
“See? See? That’s what you’ll get! I meant that! There isn’t a tribe for you any more! The conch is gone—”
After Piggy’s death, Ralph recognizes that Piggy was the one who talked sense: pg 282
What was the sensible thing to do?
There was no Piggy to talk sense. There was no solemn assembly for debate nor dignity of the conch.
At last, Ralph's reflection upon being rescued turns to Piggy: pg 290
And in the middle of them, with filthy body, matted hair, and unwiped nose, Ralph wept for the end of innocence, the darkness of man’s heart, and the fall through the air of the true, wise friend called Piggy.