碧血红天的HomePage

U3d杂谈 — 顶点纹理动画精度问题

2021-09-22

174 评论

最近再使用顶点纹理动画制作动画效果，目的是为了节省资源的消耗。但是当使用一个颜色通道存储一个Mesh顶点位置坐标的时候，发现精度是不够的，毕竟一个RGBA32的每个通道的分量是0-255。导致精度是有限的。所以这里使用一个RGBA 4个通道存储一个顶点的一个方向的坐标值。

一个float是32位的，一个RGBA32也是32位的，刚刚好能够高精度的存储下来。

基本思想，我们把32位的浮点数当做4个byte数据，存储再RGBA的4个通道中，然后在Shader中通过RGBA的4个通道的数据还原成一个float数据。

首先，float转RGBA的方法如下：

    public Color FloatToColor(float f)
    {
        byte[] buffer = BitConverter.GetBytes(f);
        int r = buffer[0];
        int g = buffer[1];
        int b = buffer[2];
        int a = buffer[3];

        return new Color((float)r / 255, (float)g / 255, (float)b / 255, (float)a / 255);
    }

在C#中把4个Byte转成Float的方法如下：

    public float ColorToFloat(Color c)
    {
        byte r = (byte)(c.r * 255);
        byte g = (byte)(c.g * 255);
        byte b = (byte)(c.b * 255);
        byte a = (byte)(c.a * 255);

        List<byte> tempList = new List<byte>();
        tempList.Add(r);
        tempList.Add(g);
        tempList.Add(b);
        tempList.Add(a);

        byte[] buffer = tempList.ToArray();
        float f = (float)BitConverter.ToSingle(buffer, 0);
        return f;
    }

但是，我们是在Shader中提取颜色，然后把一个颜色转换成一个Float数据类型，Shader中可没有方便的BitConverter方法使用，那就的我们自己通过Float的实现标准来换算出来。

//m0 是最高位  m3是最低位
float b2f(float m0, float m1, float m2, float m3)
    {
        // 求符号位
        float sig = 1;
        if (m3 >= 128.0f)
            sig = -1.0f;

        //求阶码
        float jie = 0f;
        if (m3 >= 128.0f)
        {
            jie = m3 - 128.0f;
        }
        else
        {
            jie = m3;
        }
        jie = jie * 2.0f;
        if (m2 >= 128.0f)
            jie += 1.0f;
        jie -= 127.0f;

        //求尾码

        float tail = 0.0f;
        if (m2 >= 128.0f)
            m2 -= 128.0f;
        tail = m0 + (m1 + m2 * 256.0f) * 256.0f;
        tail = (tail) / 8388608;   //   8388608 = 2^23

        float f = sig * Mathf.Pow(2.0f, jie) * (1 + tail);

        return f;
    }

然后，我们在采样的时候，3个像素值来表示一个坐标，方法如下：

v2f vert (appdata v,uint vid:SV_VertexID)
            {
                float animMap_xx = vid*3 * _AnimMap_TexelSize.x + _AnimMap_TexelSize.x / 2;
                float animMap_xy = (vid*3+1) * _AnimMap_TexelSize.x + _AnimMap_TexelSize.x / 2;
                float animMap_xz = (vid*3+2) * _AnimMap_TexelSize.x + _AnimMap_TexelSize.x / 2;
                int curFrame = int(_FrameTime %_AnimFrameCount);
                float animMap_y = (curFrame + 0.5) * _AnimMap_TexelSize.y;
                float4 pos_x = tex2Dlod(_AnimMap, float4(animMap_xx, animMap_y, 0, 0));
                float4 pos_y = tex2Dlod(_AnimMap, float4(animMap_xy, animMap_y, 0, 0));
                float4 pos_z = tex2Dlod(_AnimMap, float4(animMap_xz, animMap_y, 0, 0));
                float4 pos;
                pos.x = b2f(pos_x.x *255 , pos_x.y * 255, pos_x.z * 255, pos_x.w * 255) ;
                pos.y = b2f(pos_y.x *255 , pos_y.y * 255, pos_y.z * 255, pos_y.w * 255) ;
                pos.z = b2f(pos_z.x*255 , pos_z.y * 255, pos_z.z * 255, pos_z.w * 255) ;
                pos.w =1;
                
                v2f o;
                o.vertex = UnityObjectToClipPos(pos);

                o.uv = v.uv;
                return o;
            }

Unity3D杂谈

174 评论

  3. LagoNeeLekmc

    2022-12-04 在 11:39 上午

    ledipasvir sofosbuvir generic cost free harvoni treatment generic harvoni

    回复

  4. Kwivsibly

    2022-12-04 在 4:23 下午

    hi opp ggeis 2022 ert go fi

    回复

  6. Jonah

    2022-12-07 在 12:32 下午

    Good day! This post couldn’t be written any
    better! Reading this post reminds me of my previous room
    mate! He always kept talking about this. I will forward this article to
    him. Fairly certain he will have a good read.
    Thanks foor sharing!

    Here is my homepage; diagram maker free download – Jonah –

    回复

  7. DagoNeeLeknb

    2022-12-09 在 1:00 下午

    asunaprevir daclatasvir daklinza genotype 3 daclatasvir side effects

    回复

  9. GagoNeeLekel

    2022-12-12 在 8:51 上午

    help paying for lyrica lyrica canada lyrica 50mg

    回复

  10. Https://aaasjournal.net/

    2022-12-12 在 9:00 上午

    Appreciaqte it for this post, I am a big big fan of this website would like to proceed updated.

    Feell free to surf to my web blog answer cppc exam
    (https://aaasjournal.net/)

    回复

  11. Sherman

    2022-12-13 在 6:41 上午

    I regard somethuing genuinely special iin this web site.

    Feel free to surf to my website exasm materials preloaded (Sherman)

    回复

  13. sens-lab.org

    2022-12-15 在 12:18 上午

    Thank youu a lot for sharing this with all people you actually recognize what you aare
    talking approximately! Bookmarked. Kindly also discuss with my web sitge =).

    We may have a hyperlink trade contract between us!

    Also viskt my webpage :: police wrritten exam (sens-lab.org)

    回复

  14. Amado

    2022-12-17 在 10:54 上午

    Hmm is anyone elpse experiencing probems with the pictures on this blog loading?
    I’m trying too find out if its a problem on my end or if it’s thhe blog.
    Any feedback would be greatly appreciated.

    Feel free to visit my homepage: cpc exam questions, Amado,

    回复

  15. Joy

    2022-12-22 在 10:21 下午

    We are a gaggle of volunteers and opening a brand new scheme in oour community.
    Your sie offered us with valuable info to work on. You have perfrmed an impressive task and our entire community wilol likely be grateful to you.

    Visit my webpage pmp software (Joy)

    回复

  16. akuraschools.org

    2022-12-24 在 9:12 下午

    I have recently started a web site, the info you provide on this
    website has helped me greatly. Thanks for all off
    your time & work.

    Revie my website cisco certified (akuraschools.org)

    回复

  18. Flossie

    2022-12-28 在 6:06 上午

    Lovingg the info oon this site, you have done
    great job on tthe articles.

    My web blog – police exam (Flossie)

    回复

  19. BrendanSassy

    2022-12-28 在 10:26 下午

    Undeniably consider that which you stated. Your favorite justification seemed to be on the internet the easiest thing to take into accout of. I say to you, I certainly get irked even as folks consider issues that they plainly do not realize about. You controlled to hit the nail upon the top as smartly as defined out the whole thing with no need side-effects, other people can take a signal. Will probably be back to get more. Thank you

    https://www.deviantart.com/ruddle-digital/art/SEO-Services-UK-922584056 – deviantart.com

    回复

  21. Luz

    2022-12-30 在 4:01 上午

    Thanks for this post, I am a big big fan of this
    internet site would like to keep updated.

    Review my webpage :: cisco ccna exam, Luz,

    回复

  22. https://aaasjournal.net/

    2022-12-31 在 9:52 上午

    I have been absent for a while, but nnow I remember
    why I used to love this blog. Thank you, I’ll try and
    check back more frequently. Hoow frequently you update your website?

    Feel free to surf to my wesite :: bar exam preparation (https://aaasjournal.net/)

    回复

  23. https://sens-lab.org

    2023-01-02 在 11:11 上午

    I have recently started a site, the info you provide on this site has helped me greatly.

    Thanks for all of your time & work.

    My page: module exams (https://sens-lab.org)

    回复

  24. Kristan

    2023-01-02 在 11:13 上午

    We’re a group of volunteers and opening a brand new scheme in our
    community. Yourr website provided us with valuable info
    to work on. You have done an impressive task and our entire
    group will likely be thankful tto you.

    Here is my blog – exazm questions (Kristan)

    回复

  25. stphelps.org

    2023-01-03 在 6:57 上午

    Super-Duper website! I am loving it!! Willl be back later to read some more.
    I am bookmarking your feedxs also

    Feel free to surf to my web blog … exzam material typically – stphelps.org –

    回复

  26. Trent

    2023-01-09 在 9:27 上午

    I am sure this piece of writing has touched alll the internet visitors, its really really pleasant post on building upp new weblog.

    Also visit my web blog; pmp simulator – Trent –

    回复

  27. aaasjournal.net

    2023-01-09 在 1:01 下午

    Loving the info on this website, you have
    done great job on tthe bllg posts.

    Feel free to visit my web site :: police jobs [aaasjournal.net]

    回复

  28. Margarito

    2023-01-13 在 8:05 下午

    Thank you, I have recently been searching for info approximately this subject for a while and yours is the greatest I have came upon so far.
    However, what concerning the conclusion? Are you sure about the
    source?

    Look at my web blog – pmp 35 pdu (Margarito)

    回复

  31. Jrnaquamilip

    2023-01-20 在 5:22 上午

    tadalafil sublingual tablet 20mg cialis daily online viagra levitra cialis which works better?

    回复

  32. Knnfsibly

    2023-01-20 在 5:22 上午

    tadalafil 20 mg dosage cialis side effects forum canadian drugstore cialis

    回复

  33. EbxdMaype

    2023-01-20 在 5:44 上午

    cheap generic viagra from india viagra 50 mg tablet online purchase cheap viagra mastercard

    回复

  34. Wooladoms

    2023-01-20 在 10:51 上午

    where to buy viagra over the counter sildenafil 50 mg online uk cheap viagra uk

    回复

  36. QuuMaype

    2023-01-20 在 6:06 下午

    tadalafil without a prescription cialis canada pharmacy tadalafil and blood pressure

    回复

  37. TujMaype

    2023-01-21 在 4:00 上午

    people’s pharmacy synthroid real viagra online canadian pharmacy popular prescription drugs

    回复

  38. Jnebadoms

    2023-01-21 在 7:21 下午

    giant pharmacy reliable rx pharmacy walmart pharmacy enalapril

    回复

  39. Jbqaquamilip

    2023-01-21 在 7:33 下午

    walgreens pharmacy near me canadian pharmacy east bay largo fl cedarwood pharmacy canada

    回复

  40. EexdMaype

    2023-01-21 在 8:42 下午

    canadian pharmacy viagra cialis troy pharmacy tramadol cod compounding pharmacy viagra

    回复

  41. AmvtGlync

    2023-01-21 在 11:07 下午

    optum rx pharmacy help desk canadian pharmacy locations most reputable canadian pharmacy

    回复

  42. QubMaype

    2023-01-22 在 6:29 上午

    fry’s pharmacy la canada and lambert prometrium canadian pharmacy cost of levitra at walmart pharmacy

    回复

  43. Woroladoms

    2023-01-22 在 9:29 上午

    pharmacy viagra sans ordonnance canadian pharmacy azithromycin effexor xr pharmacy

    回复

  44. Inge

    2023-01-26 在 2:48 上午

    I am impressed with this site, real I am a big fan.

    Here is my wweb page; certificatiin questions (Inge)

    回复

  46. Jmeuadoms

    2023-01-26 在 6:26 下午

    purchase viagra over the counter best prices for viagra prescription coupon sildenafil 20mg

    回复

  47. Kensibly

    2023-01-26 在 7:23 下午

    discount online viagra generic viagra no prescription viagra otc in canada

    回复

  48. Jemtaquamilip

    2023-01-26 在 7:24 下午

    cialis viagra levitra canada get cialis online cialis samples free

    回复

  50. QemmMaype

    2023-01-28 在 12:04 上午

    generic viagra pills for sale cheap viagra free shipping viagra tablet

    回复

  51. EhdMaype

    2023-01-28 在 4:03 上午

    generic viagra online fast delivery viagra pills online canada where can i get female viagra uk

    回复

  52. AmrbGlync

    2023-01-28 在 6:25 上午

    genuine viagra canada purchase genuine viagra generic viagra – mastercard

    回复

  53. TmrbMaype

    2023-01-28 在 7:05 上午

    what is cialis black 800mg cialis 36 hour online super tadalafil with dapoxetine

    回复

  54. Knrsibly

    2023-01-28 在 5:23 下午

    tadalafil generico tadalafil order buy cialis no prescription

    回复

  55. Jdnvadoms

    2023-01-28 在 5:33 下午

    cialis 5mg no prescription online cialis canada cialis canada over the counter

    回复

  57. Wdbladoms

    2023-01-29 在 7:30 上午

    brands of generic tadalafil cialis contraindications generic tadalafil canada

    回复

  58. ThwMaype

    2023-01-29 在 5:21 下午

    cialis otc usa when will generic cialis be available cialis australia express shipping

    回复

  59. Jdnvadoms

    2023-01-29 在 8:25 下午

    sublingual tadalafil buy cialis 20 mg tadalafil alternative

    回复

  60. EhdMaype

    2023-01-30 在 5:30 上午

    generic sildenafil online sildenafil 100mg buy online viagra tablet

    回复

  62. Reyes

    2023-01-30 在 7:14 下午

    I’m no longer positive where you’re getting
    your info, but good topic. I must spend some time studying much more or understanding more.
    Thank yyou for great info I used to be searching for
    this info for my mission.

    Also visit my web-site – written driving exam (Reyes)

    回复

  63. Wdbladoms

    2023-01-31 在 5:14 上午

    how much cialis should i take cialis daily vs regular cialis walmart price for cialis

    回复

  64. Nannette

    2023-02-08 在 11:38 下午

    Hmm is anyone else encountering problems with the pictures on this blog loading?
    I’m trying to figure out if its a problem on my end or if it’s
    the blog.Any suggestions would be greatly appreciated.

    My webpage: ppmp software (Nannette)

    回复

  65. SagoNeeLekbh

    2023-02-09 在 5:48 下午

    furosemide 40 mg para que sirve what is furosemide what is lasix

    回复

  66. Jttadoms

    2023-02-11 在 12:27 上午

    metformin melasma metformin analysis dauerdurchfall metformin

    回复

  67. TooMaype

    2023-02-11 在 1:52 上午

    lisinopril lexapro lisinopril omeprazole lisinopril breastfeeding

    回复

  68. EtnMaype

    2023-02-11 在 9:00 上午

    utilisation flagyl metrogyl flagyl metronidazole image

    回复

  69. AtnGlync

    2023-02-11 在 11:11 上午

    tenormin ivz atenolol respiratory atenolol spironolactone

    回复

  70. QneMaype

    2023-02-11 在 7:19 下午

    furosemide journals lasix insert lasix rash

    回复

  76. AtnGlync

    2023-02-13 在 5:52 上午

    atenolol mood atenolol thirsty atenolol therabloc

    回复

  77. Wyhladoms

    2023-02-13 在 8:22 上午

    tamoxifen behandlingstid tamoxifen innemen nolvadex laws

    回复

  80. QneMaype

    2023-02-15 在 10:58 上午

    lasix medicines lasix cad adjusting lasix

    回复

  81. Jnnadoms

    2023-02-15 在 11:42 下午

    synthroid pronunciation synthroid medicinenet administering synthroid

    回复

  82. AefGlync

    2023-02-16 在 11:01 上午

    pregabalin withdrawal reviews what does lyrica do to you lyrica dose

    回复

  85. QubMaype

    2023-02-16 在 6:34 下午

    trazodone haldol trazodone white trazodone venezuela

    回复

  86. TzqMaype

    2023-02-17 在 12:57 上午

    furosemide werkingsduur lasix shape lasix msds

    回复

  87. Jnnadoms

    2023-02-17 在 1:08 上午

    synthroid sudafed warfarin synthroid aspirin synthroid

    回复

  88. AefGlync

    2023-02-17 在 10:42 上午

    pregabalin good rx how much lyrica to get high pregabalin for seizures

    回复

  89. Wrnadoms

    2023-02-17 在 2:20 下午

    bactrim valtrex malarone valtrex valtrex hepatitis

    回复

  90. Tzqclems

    2023-02-17 在 8:49 下午

    metformin liraglutide metformin nierenversagen metformin gynaecology

    回复

  91. JnnOpilt

    2023-02-17 在 9:01 下午

    bnf lisinopril lisinopril laryngitis lisinopril vs avalide

    回复

  93. EnrHycle

    2023-02-18 在 7:04 上午

    tenormin and aspirin tenormin safe dose atenolol adderall

    回复

  95. Aefpoolf

    2023-02-18 在 9:14 上午

    trazodone pharmacodynamics trazodone barr trazodone agoraphobia

    回复

  97. WrnBoype

    2023-02-18 在 5:32 下午

    nejm atorvastatin lipitor obat atorvastatin potenz

    回复

  99. EnrHycle

    2023-02-19 在 4:29 下午

    atenolol pheochromocytoma atenolol concentration atenolol exhaustion

    回复

  101. JnnOpilt

    2023-02-19 在 8:39 下午

    lisinopril mental health lisinopril swallowing sinopren lisinopril

    回复

  102. Tzqclems

    2023-02-19 在 9:46 下午

    metformin hwz metformin cream metformin koloskopie

    回复

  104. EdfHycle

    2023-02-20 在 7:38 上午

    synthroid mania organic synthroid synthroid overdoses

    回复

  106. WrfvBoype

    2023-02-20 在 2:48 下午

    pregabalin 50mg pregabalin 25 mg price pregabalin 150 mg cost

    回复

  107. QvaWaity

    2023-02-20 在 9:09 下午

    neurontin and citalopram neurontin and hypertension gabapentin powder

    回复

  109. Ferne

    2023-02-21 在 3:27 上午

    I’ll right away snatch your rsss ass I can’t
    find your email subscription hyperlink or newsletter service.
    Do you’ve any? Please permit me understand in order
    that I may just subscribe. Thanks.

    Also visit my web site exam material (Ferne)

    回复

  110. Aespoolf

    2023-02-21 在 3:52 上午

    metronidazole pgd flagyl lepistes flagyl apresentacoes

    回复

  112. SagoNeeLekqo

    2023-02-21 在 11:23 上午

    ivermectin dog dosage pyrantel ivermectin stromectol 3 mg tablet

    回复

  114. WrfvBoype

    2023-02-21 在 7:37 下午

    pregabalin 100mg capsules best dose of pregabalin for anxiety side effects of lyrica

    回复

  115. QvaWaity

    2023-02-21 在 9:38 下午

    occipital neuralgia neurontin gabapentin greyhound neurontin causes neuropathy

    回复

  118. then stake it in Syrup Pools to earn more tokens!

    2023-02-23 在 3:14 下午

    I think the admin of this site is truly working hard in favor of his website, for the reason that here every data is quality based stuff.
    then stake it in Syrup Pools to earn more tokens! Win millions in prizes

    回复

  123. JnwOpilt

    2023-02-28 在 5:40 上午

    comparative essay example write my essay for cheap the best way to ensure parallel construction in your essay is to use similar

    回复

  124. EdfsHycle

    2023-02-28 在 12:10 下午

    essay proposal example college admission essay help character analysis essay example

    回复

  125. Ahrspoolf

    2023-02-28 在 2:24 下午

    thesis statement in an essay sat essay tips respond essay

    回复

  126. WnsBoype

    2023-02-28 在 7:45 下午

    essay writer software citations in an essay essay title page

    回复

  127. QnwWaity

    2023-02-28 在 11:41 下午

    essay writing website essay help online essay writers

    回复

  128. takipçi satın al ucuz

    2023-03-01 在 4:19 上午

    En iyi takipç isitesinden takipçi satın al ucuza ;https://rebrand.ly/2d8aee

    回复

  129. Tcctclems

    2023-03-01 在 5:57 上午

    best college essay service editing essay services college essay help nyc

    回复

  132. EddHycle

    2023-03-01 在 4:15 下午

    auto essay writer cyber bullying essay buy cheap essays

    回复

  133. WwnBoype

    2023-03-01 在 7:32 下午

    where to buy college research papers writing a research paper in apa format professional paper writing services

    回复

  135. QjfWaity

    2023-03-02 在 5:28 上午

    academic essay help what is a claim in an essay custom essay writing canada

    回复

  137. Thwcclems

    2023-03-02 在 5:50 下午

    decorative writing paper printable horizontal writing paper custom written paper

    回复

  138. JzzqOpilt

    2023-03-02 在 5:59 下午

    which of the following are best practices when writing the first draft of a research paper? writing a college paper help with writing a paper for college

    回复

  139. EoopHycle

    2023-03-03 在 2:52 上午

    printing writing paper writing paper for kindergarten imagine you are writing a research paper on social networking sites which of the following thesis

    回复

  140. WxedBoype

    2023-03-03 在 7:50 上午

    chinese writing paper lined paper for second grade writing write my paper for money

    回复

  141. QhrWaity

    2023-03-03 在 1:23 下午

    primary writing paper with picture box free writing paper to print writing paper 1st grade

    回复

  142. Aybvpoolf

    2023-03-03 在 4:09 下午

    online paper writing service paper writing sites printable writing paper with border

    回复

  143. Tnssclems

    2023-03-04 在 10:52 下午

    thesis paper writing service designed paper for writing printable free writing paper with picture box pdf

    回复

  144. JntjOpilt

    2023-03-04 在 11:04 下午

    literature review for dissertation dissertation proposal digital dissertations

    回复

  145. SagoNeeLekab

    2023-03-05 在 3:32 上午

    ivermectin tractor supply pyrantel ivermectin ivermectin side effects in dogs

    回复

  146. WikkBoype

    2023-03-05 在 1:07 下午

    best dissertation services cornell dissertation how many pages should a dissertation be

    回复

  147. Adnvpoolf

    2023-03-05 在 6:02 下午

    rackham dissertation deadlines dissertation proposal writing service dissertation examples in education

    回复

  148. Tnssclems

    2023-03-06 在 7:01 上午

    do my papers bee writing paper professional paper writer

    回复

  149. JntjOpilt

    2023-03-06 在 7:12 上午

    higher education dissertation topics how long is a dissertation for phd dissertation literature review

    回复

  150. Tnssclems

    2023-03-08 在 4:11 上午

    college paper writers lined writing paper templates buying papers online

    回复

  151. JntjOpilt

    2023-03-08 在 4:21 上午

    citing a dissertation mla doctoral dissertation writing help acls dissertation completion fellowship

    回复

  152. EncxHycle

    2023-03-08 在 1:08 下午

    dissertation help reviews dissertation topic how to ask someone to be on your dissertation committee

    回复

  153. Adnvpoolf

    2023-03-08 在 3:18 下午

    dissertation reviewer how long to write dissertation e thesis and dissertation

    回复

  154. WikkBoype

    2023-03-08 在 7:06 下午

    help writing dissertation proposal dissertation topics writing your dissertation in 15 minutes a day

    回复

  155. EagoNeeLekyj

    2023-03-09 在 1:50 上午

    stromectol ivermectin for dogs ivermectin toxicity in dogs

    回复

  156. Tujclems

    2023-03-09 在 6:17 下午

    admission essay writing services cheap essay service custom essays no plagiarism

    回复

  157. JrjbOpilt

    2023-03-09 在 6:34 下午

    assignment essay help custom essay writing reviews write my essay today

    回复

  158. EybvHycle

    2023-03-10 在 3:21 上午

    help me write an essay buy essays for college college admission essay help

    回复

  159. Aybapoolf

    2023-03-10 在 5:46 上午

    online essay writing help help essay 123 help for essay writing

    回复

  160. WuqBoype

    2023-03-10 在 6:06 上午

    best essay writers online recommended essay writing service will someone write my essay for me

    回复

  162. JrjbOpilt

    2023-03-11 在 3:49 上午

    top rated essay writing services websites for essay writing essay introduction help

    回复

  164. Aybapoolf

    2023-03-11 在 5:28 下午

    can someone write my essay online essay writing help essay help websites

    回复

  165. WuqBoype

    2023-03-11 在 6:25 下午

    essay revision help online what are good essay writing services help write my essay

    回复

  166. EagoNeeLekba

    2023-03-11 在 11:43 下午

    stromectol over the counter ivermectin pour on oral ivermectin for rosacea

    回复

  167. QnehWaity

    2023-03-11 在 11:54 下午

    personal essay help best essay for you cheap essay writing service usa

    回复

发表评论