Textured glass refraction and transparency












0















I am trying to create a shader that would allow a sprite to both slightly magnify (or just offset a bit) its background and showing its texture at the same same, just like a piece of painted glass would do.
I found a shader that almost does it, however it also changes the background based on how bright the upper layer/sprite is:



sampler2D img;
sampler2D bkd : register(s1);

float4 ps_main(in float2 In: TEXCOORD0) : COLOR0 {
float4 L = tex2D(img,In);
float4 B = tex2D(bkd,In);
return (L<0.5)?min(B,(2.0*L)):max(B,(2.0*(L-0.5)));
}

technique tech_main { pass P0 { PixelShader = compile ps_2_0 ps_main(); } }


I tried to modify the parameters but the results are awful.










share|improve this question



























    0















    I am trying to create a shader that would allow a sprite to both slightly magnify (or just offset a bit) its background and showing its texture at the same same, just like a piece of painted glass would do.
    I found a shader that almost does it, however it also changes the background based on how bright the upper layer/sprite is:



    sampler2D img;
    sampler2D bkd : register(s1);

    float4 ps_main(in float2 In: TEXCOORD0) : COLOR0 {
    float4 L = tex2D(img,In);
    float4 B = tex2D(bkd,In);
    return (L<0.5)?min(B,(2.0*L)):max(B,(2.0*(L-0.5)));
    }

    technique tech_main { pass P0 { PixelShader = compile ps_2_0 ps_main(); } }


    I tried to modify the parameters but the results are awful.










    share|improve this question

























      0












      0








      0








      I am trying to create a shader that would allow a sprite to both slightly magnify (or just offset a bit) its background and showing its texture at the same same, just like a piece of painted glass would do.
      I found a shader that almost does it, however it also changes the background based on how bright the upper layer/sprite is:



      sampler2D img;
      sampler2D bkd : register(s1);

      float4 ps_main(in float2 In: TEXCOORD0) : COLOR0 {
      float4 L = tex2D(img,In);
      float4 B = tex2D(bkd,In);
      return (L<0.5)?min(B,(2.0*L)):max(B,(2.0*(L-0.5)));
      }

      technique tech_main { pass P0 { PixelShader = compile ps_2_0 ps_main(); } }


      I tried to modify the parameters but the results are awful.










      share|improve this question














      I am trying to create a shader that would allow a sprite to both slightly magnify (or just offset a bit) its background and showing its texture at the same same, just like a piece of painted glass would do.
      I found a shader that almost does it, however it also changes the background based on how bright the upper layer/sprite is:



      sampler2D img;
      sampler2D bkd : register(s1);

      float4 ps_main(in float2 In: TEXCOORD0) : COLOR0 {
      float4 L = tex2D(img,In);
      float4 B = tex2D(bkd,In);
      return (L<0.5)?min(B,(2.0*L)):max(B,(2.0*(L-0.5)));
      }

      technique tech_main { pass P0 { PixelShader = compile ps_2_0 ps_main(); } }


      I tried to modify the parameters but the results are awful.







      shader hlsl






      share|improve this question













      share|improve this question











      share|improve this question




      share|improve this question










      asked Jan 2 at 12:42









      John VJohn V

      2,02482546




      2,02482546
























          1 Answer
          1






          active

          oldest

          votes


















          1














          To combine the textures, either lerp between B and L, or lerp between B and L*B. You can expose the lerp factor as a uniform for control.



          For the magnification, you want to scale the UV coordinates of the background texture in the texture lookup. Just scaling it outright won't work though, you need to get the distance between the UV coordinates of your screen buffer sample and the center of your magnifying glass, scale that, then add it to your original UV coordinates.



          Here is a short magnifying glass shader on shadertoy showing you what i mean (in GLSL):



          https://www.shadertoy.com/view/lsjczh






          share|improve this answer























            Your Answer






            StackExchange.ifUsing("editor", function () {
            StackExchange.using("externalEditor", function () {
            StackExchange.using("snippets", function () {
            StackExchange.snippets.init();
            });
            });
            }, "code-snippets");

            StackExchange.ready(function() {
            var channelOptions = {
            tags: "".split(" "),
            id: "1"
            };
            initTagRenderer("".split(" "), "".split(" "), channelOptions);

            StackExchange.using("externalEditor", function() {
            // Have to fire editor after snippets, if snippets enabled
            if (StackExchange.settings.snippets.snippetsEnabled) {
            StackExchange.using("snippets", function() {
            createEditor();
            });
            }
            else {
            createEditor();
            }
            });

            function createEditor() {
            StackExchange.prepareEditor({
            heartbeatType: 'answer',
            autoActivateHeartbeat: false,
            convertImagesToLinks: true,
            noModals: true,
            showLowRepImageUploadWarning: true,
            reputationToPostImages: 10,
            bindNavPrevention: true,
            postfix: "",
            imageUploader: {
            brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
            contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
            allowUrls: true
            },
            onDemand: true,
            discardSelector: ".discard-answer"
            ,immediatelyShowMarkdownHelp:true
            });


            }
            });














            draft saved

            draft discarded


















            StackExchange.ready(
            function () {
            StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f54006610%2ftextured-glass-refraction-and-transparency%23new-answer', 'question_page');
            }
            );

            Post as a guest















            Required, but never shown

























            1 Answer
            1






            active

            oldest

            votes








            1 Answer
            1






            active

            oldest

            votes









            active

            oldest

            votes






            active

            oldest

            votes









            1














            To combine the textures, either lerp between B and L, or lerp between B and L*B. You can expose the lerp factor as a uniform for control.



            For the magnification, you want to scale the UV coordinates of the background texture in the texture lookup. Just scaling it outright won't work though, you need to get the distance between the UV coordinates of your screen buffer sample and the center of your magnifying glass, scale that, then add it to your original UV coordinates.



            Here is a short magnifying glass shader on shadertoy showing you what i mean (in GLSL):



            https://www.shadertoy.com/view/lsjczh






            share|improve this answer




























              1














              To combine the textures, either lerp between B and L, or lerp between B and L*B. You can expose the lerp factor as a uniform for control.



              For the magnification, you want to scale the UV coordinates of the background texture in the texture lookup. Just scaling it outright won't work though, you need to get the distance between the UV coordinates of your screen buffer sample and the center of your magnifying glass, scale that, then add it to your original UV coordinates.



              Here is a short magnifying glass shader on shadertoy showing you what i mean (in GLSL):



              https://www.shadertoy.com/view/lsjczh






              share|improve this answer


























                1












                1








                1







                To combine the textures, either lerp between B and L, or lerp between B and L*B. You can expose the lerp factor as a uniform for control.



                For the magnification, you want to scale the UV coordinates of the background texture in the texture lookup. Just scaling it outright won't work though, you need to get the distance between the UV coordinates of your screen buffer sample and the center of your magnifying glass, scale that, then add it to your original UV coordinates.



                Here is a short magnifying glass shader on shadertoy showing you what i mean (in GLSL):



                https://www.shadertoy.com/view/lsjczh






                share|improve this answer













                To combine the textures, either lerp between B and L, or lerp between B and L*B. You can expose the lerp factor as a uniform for control.



                For the magnification, you want to scale the UV coordinates of the background texture in the texture lookup. Just scaling it outright won't work though, you need to get the distance between the UV coordinates of your screen buffer sample and the center of your magnifying glass, scale that, then add it to your original UV coordinates.



                Here is a short magnifying glass shader on shadertoy showing you what i mean (in GLSL):



                https://www.shadertoy.com/view/lsjczh







                share|improve this answer












                share|improve this answer



                share|improve this answer










                answered Jan 7 at 14:28









                Kalle HalvarssonKalle Halvarsson

                381210




                381210
































                    draft saved

                    draft discarded




















































                    Thanks for contributing an answer to Stack Overflow!


                    • Please be sure to answer the question. Provide details and share your research!

                    But avoid



                    • Asking for help, clarification, or responding to other answers.

                    • Making statements based on opinion; back them up with references or personal experience.


                    To learn more, see our tips on writing great answers.




                    draft saved


                    draft discarded














                    StackExchange.ready(
                    function () {
                    StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f54006610%2ftextured-glass-refraction-and-transparency%23new-answer', 'question_page');
                    }
                    );

                    Post as a guest















                    Required, but never shown





















































                    Required, but never shown














                    Required, but never shown












                    Required, but never shown







                    Required, but never shown

































                    Required, but never shown














                    Required, but never shown












                    Required, but never shown







                    Required, but never shown







                    Popular posts from this blog

                    MongoDB - Not Authorized To Execute Command

                    How to fix TextFormField cause rebuild widget in Flutter

                    in spring boot 2.1 many test slices are not allowed anymore due to multiple @BootstrapWith