📄 getteximage.ps
字号:
1724 0.4531(reference)AX2047(pages)X3 f2252(glTexImage1D)X1 f2777(and)X3 f2915(glDrawPixels)X1 f3391(for)X3507(a)X3565(description)X3943(of)X554 3914(the)N672(acceptable)X1032(values)X1257(for)X1371(the)X2 f1489(format)X1 f1722(and)X2 f1858(type)X1 f2012(parameters,)X2405(respectively.)X554 4048(To)N677(understand)X1063(the)X1196(operation)X1534(of)X3 f1636(glGetTexImage)X1 f2166(,)X2221(consider)X2528(the)X2661(selected)X2955(internal)X3235(four-component)X3787(texture)X554 4144(image)N771(to)X854(be)X951(an)X1048(RGBA)X1291(color)X1477(buffer)X1695(the)X1814(size)X1960(of)X2048(the)X2167(image.)X2424(The)X2570(semantics)X2907(of)X3 f2995(glGetTexImage)X1 f3546(are)X3665(then)X3823(ident-)X554 4240(ical)N695(to)X782(those)X976(of)X3 f1068(glReadPixels)X1 f1533(called)X1750(with)X1917(the)X2040(same)X2 f2230(format)X1 f2468(and)X2 f2609(type)X1 f2743(,)X2788(with)X2 f2955(x)X1 f3016(and)X2 f3157(y)X1 f3218(set)X3332(to)X3420(0,)X2 f3506(width)X1 f3709(set)X3824(to)X3912(the)X554 4336(width)N759(of)X849(the)X970(texture)X1216(image)X1435(\(including)X1787(border)X2020(if)X2092(one)X2231(was)X2379(speci\256ed\),)X2734(and)X2 f2873(height)X1 f3096(set)X3208(to)X3292(1)X3354(for)X3470(1D)X3590(images,)X3859(or)X3948(to)X554 4432(the)N673(height)X894(of)X982(the)X1101(texture)X1345(image)X1562(\(including)X1912(border)X2143(if)X2213(one)X2350(was)X2496(speci\256ed\))X2830(for)X2946(2D)X3066(images.)X3355(Because)X3645(the)X3765(internal)X554 4528(texture)N813(image)X1045(is)X1134(an)X1246(RGBA)X1504(image,)X1756(pixel)X1952(formats)X3 f2233(GL_COLOR_INDEX)X1 f2979(,)X3 f3035(GL_STENCIL_INDEX)X1 f3838(,)X3894(and)X3 f554 4624(GL_DEPTH_COMPONENT)N1 f1573(are)X1692(not)X1814(accepted,)X2136(and)X2272(pixel)X2452(type)X3 f2610(GL_BITMAP)X1 f3105(is)X3178(not)X3300(accepted.)X554 4758(If)N645(the)X780(selected)X1076(texture)X1336(image)X1569(does)X1753(not)X1892(contain)X2166(four)X2338(components,)X2783(the)X2919(following)X3268(mappings)X3617(are)X3754(applied.)X554 4854(Single-component)N1166(textures)X1445(are)X1569(treated)X1812(as)X1903(RGBA)X2149(buffers)X2401(with)X2567(red)X2694(set)X2807(to)X2893(the)X3015(single-component)X3613(value,)X3831(green)X554 4950(set)N667(to)X753(0,)X857(blue)X1019(set)X1132(to)X1218(0,)X1302(and)X1442(alpha)X1640(set)X1754(to)X1841(1.)X1946(Two-component)X2501(textures)X2780(are)X2904(treated)X3148(as)X3240(RGBA)X3487(buffers)X3740(with)X3907(red)X554 5046(set)N669(to)X757(the)X881(value)X1081(of)X1174(component)X1556(zero,)X1741(alpha)X1941(set)X2056(to)X2144(the)X2267(value)X2466(of)X2558(component)X2939(one,)X3100(and)X3241(green)X3445(and)X3586(blue)X3749(set)X3863(to)X3950(0.)X554 5142(Finally,)N821(three-component)X1386(textures)X1661(are)X1781(treated)X2021(as)X2109(RGBA)X2352(buffers)X2601(with)X2764(red)X2888(set)X2998(to)X3081(component)X3458(zero,)X3638(green)X3838(set)X3948(to)X554 5238(component)N930(one,)X1086(blue)X1244(set)X1353(to)X1435(component)X1811(two,)X1971(and)X2107(alpha)X2301(set)X2410(to)X2492(1.)X554 5372(To)N664(determine)X1006(the)X1125(required)X1414(size)X1560(of)X2 f1648(pixels)X1 f1835(,)X1876(use)X3 f2004 0.1786(glGetTexLevelParameter)AX1 f2895(to)X2978(determine)X3320(the)X3439(dimensions)X3824(of)X3912(the)X554 5468(internal)N831(texture)X1086(image,)X1334(then)X1504(scale)X1697(the)X1827(required)X2127(number)X2404(of)X2502(pixels)X2724(by)X2835(the)X2964(storage)X3227(required)X3526(for)X3651(each)X3830(pixel,)X554 5564(based)N784(on)X2 f911(format)X1 f1171(and)X2 f1334(type)X1 f1468(.)X1555(Be)X1691(sure)X1872(to)X1982(take)X2164(the)X2310(pixel)X2518(storage)X2798(parameters)X3199(into)X3371(account,)X3689(especially)X3 f554 5660(GL_PACK_ALIGNMENT)N1 f1478(.)X266 6144(Page)N442(1)X3577(July)X3730(22,)X3850(1997)X2 p%%Page: 2 210 s 0 xH 0 xS 1 f10 f0 96(h)N24(hhh)X4176(h)X4200(hhh)X9 s1 f266 480(G)N268(GL)X322(LG)X368(GE)X422(ET)X468(TT)X514(TE)X560(EX)X606(XI)X660(IM)X686(MA)X752(AG)X806(GE)X860(E)X910(\()X912(\()X948(\))X950(\))X1885(U)X1887(UN)X1941(NI)X1995(IX)X2021(X)X2093(S)X2095(Sy)X2137(ys)X2175(st)X2205(te)X2227(em)X2261(m)X2337(V)X2339(V)X3302(G)X3304(GL)X3358(LG)X3404(GE)X3458(ET)X3504(TT)X3550(TE)X3596(EX)X3642(XI)X3696(IM)X3722(MA)X3788(AG)X3842(GE)X3896(E)X3946(\()X3948(\()X3984(\))X3986(\))X266 864(N)N268(NO)X322(OT)X376(TE)X422(ES)X468(S)X10 s554 960(If)N628(an)X724(error)X901(is)X974(generated,)X1327(no)X1427(change)X1675(is)X1748(made)X1942(to)X2024(the)X2142(contents)X2429(of)X2 f2516(pixels)X1 f2703(.)X9 s266 1094(E)N268(ER)X314(RR)X364(RO)X414(OR)X468(RS)X518(S)X3 f10 s554 1190(GL_INVALID_ENUM)N1 f1361(is)X1434(generated)X1767(if)X2 f1836(target)X1 f2027(,)X2 f2067(format)X1 f2280(,)X2320(or)X2 f2407(type)X1 f2561(is)X2634(not)X2756(an)X2852(accepted)X3154(value.)X3 f554 1324(GL_INVALID_VALUE)N1 f1396(is)X1469(generated)X1802(if)X2 f1871(level)X1 f2043(is)X2116(less)X2256(than)X2414(0.)X3 f554 1458(GL_INVALID_VALUE)N1 f1403(may)X1568(be)X1671(generated)X2011(if)X2 f2087(level)X1 f2266(is)X2346(greater)X2597(than)X2762($log)X2931(sub)X3069(2)X3136(max$,)X3361(where)X3585($max$)X3831(is)X3912(the)X554 1554(returned)N842(value)X1036(of)X3 f1123(GL_MAX_TEXTURE_SIZE)X1 f2117(.)X3 f554 1688(GL_INVALID_OPERATION)N1 f1600(is)X1673(generated)X2006(if)X3 f2075(glGetTexImage)X1 f2625(is)X2698(executed)X3004(between)X3292(the)X3411(execution)X3744(of)X3 f3832(glBe-)X554 1784(gin)N1 f680(and)X816(the)X934(corresponding)X1413(execution)X1745(of)X3 f1832(glEnd)X1 f2035(.)X9 s266 1918(A)N268(AS)X322(SS)X364(SO)X406(OC)X460(CI)X510(IA)X536(AT)X590(TE)X636(ED)X682(D)X766(G)X768(GE)X822(ET)X868(TS)X914(S)X3 f10 s554 2014 0.1786(glGetTexLevelParameter)AN1 f1444(with)X1606(argument)X3 f1929(GL_TEXTURE_WIDTH)X554 2110 0.1786(glGetTexLevelParameter)AN1 f1444(with)X1606(argument)X3 f1929(GL_TEXTURE_HEIGHT)X554 2206 0.1786(glGetTexLevelParameter)AN1 f1444(with)X1606(argument)X3 f1929(GL_TEXTURE_BORDER)X554 2302 0.1786(glGetTexLevelParameter)AN1 f1444(with)X1606(argument)X3 f1929(GL_TEXTURE_COMPONENTS)X554 2398(glGet)N1 f761(with)X923(arguments)X3 f1277(GL_PACK_ALIGNMENT)X1 f2221(and)X2357(others)X9 s266 2532(S)N268(SE)X310(EE)X356(E)X432(A)X434(AL)X488(LS)X534(SO)X576(O)X3 f10 s554 2628(glDrawPixels)N1 f1008(,)X3 f1048(glReadPixels)X1 f(,)S3 f1528(glTexEnv)X1 f1856(,)X3 f1896(glTexGen)X1 f2229(,)X3 f2269(glTexImage1D)X1 f2772(,)X3 f2812(glTexImage2D)X1 f3315(,)X3 f3355(glTexSubImage1D)X1 f3990(,)X3 f554 2724(glTexSubImage2D)N1 f1189(,)X3 f1229(glTexParameter)X1 f266 6144(July)N419(22,)X539(1997)X3794(Page)X3970(2)X10 f0 6428(h)N24(hhh)X4176(h)X4200(hhh)X2 p%%Trailerxtxs
⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -