Shader on video

[feelixe]

Hey, I just tried applying a Blur Shader to a video, but insted of seing the video I just see some text.
Is this a limitation or did i do something wrong?

[Nixola]

Could you share a love file?

[feelixe]

Could you share a love file?

I Found this shader in the forums. I tried without the canvas first but that didn't work.

Code: Select all

	video1 = love.graphics.newVideo("images/Wildlife.ogv",false),
	blur1 = love.graphics.newShader [[

      vec4 effect(vec4 color, Image texture, vec2 vTexCoord, vec2 pixel_coords)
      {
         vec4 sum = vec4(0.0);
         number blurSize = 0.005;
         //number d = distance(vTexCoord, mousePos/screenSize);
         //number blurSize = clamp(1/d/screenSize.x, 0, 1.0);
         // blur in y (vertical)
         // take nine samples, with the distance blurSize between them
         sum += texture2D(texture, vec2(vTexCoord.x - 4.0*blurSize, vTexCoord.y)) * 0.05;
         sum += texture2D(texture, vec2(vTexCoord.x - 3.0*blurSize, vTexCoord.y)) * 0.09;
         sum += texture2D(texture, vec2(vTexCoord.x - 2.0*blurSize, vTexCoord.y)) * 0.12;
         sum += texture2D(texture, vec2(vTexCoord.x - blurSize, vTexCoord.y)) * 0.15;
         sum += texture2D(texture, vec2(vTexCoord.x, vTexCoord.y)) * 0.16;
         sum += texture2D(texture, vec2(vTexCoord.x + blurSize, vTexCoord.y)) * 0.15;
         sum += texture2D(texture, vec2(vTexCoord.x + 2.0*blurSize, vTexCoord.y)) * 0.12;
         sum += texture2D(texture, vec2(vTexCoord.x + 3.0*blurSize, vTexCoord.y)) * 0.09;
         sum += texture2D(texture, vec2(vTexCoord.x + 4.0*blurSize, vTexCoord.y)) * 0.05;
         
         
         return sum;
      }
      ]],
	  blur2 = love.graphics.newShader [[
      
      vec4 effect(vec4 color, Image texture, vec2 vTexCoord, vec2 pixel_coords)
      {
         vec4 sum = vec4(0.0);
         number blurSize = 0.005;

         // blur in y (vertical)
         // take nine samples, with the distance blurSize between them
         sum += texture2D(texture, vec2(vTexCoord.x, vTexCoord.y - 4.0*blurSize)) * 0.05;
         sum += texture2D(texture, vec2(vTexCoord.x, vTexCoord.y - 3.0*blurSize)) * 0.09;
         sum += texture2D(texture, vec2(vTexCoord.x, vTexCoord.y - 2.0*blurSize)) * 0.12;
         sum += texture2D(texture, vec2(vTexCoord.x, vTexCoord.y- blurSize)) * 0.15;
         sum += texture2D(texture, vec2(vTexCoord.x, vTexCoord.y)) * 0.16;
         sum += texture2D(texture, vec2(vTexCoord.x, vTexCoord.y + blurSize)) * 0.15;
         sum += texture2D(texture, vec2(vTexCoord.x, vTexCoord.y + 2.0*blurSize)) * 0.12;
         sum += texture2D(texture, vec2(vTexCoord.x, vTexCoord.y + 3.0*blurSize)) * 0.09;
         sum += texture2D(texture, vec2(vTexCoord.x, vTexCoord.y + 4.0*blurSize)) * 0.05;

         return sum;
      }
      ]]

Code: Select all

love.graphics.setCanvas(canvas)
	love.graphics.setShader(images.blur1)
	love.graphics.draw(images.video1,0,0,0,2,2)
	love.graphics.setShader()
	love.graphics.setCanvas()
	love.graphics.setShader(images.blur2)
	love.graphics.draw(canvas,0,0)
	love.graphics.setShader()

[slime]

To get a pixel's color directly from a Video, you have to use VideoTexel(texcoord) instead of Texel/texture2D(texture, texcoord), since the Video object is not a Texture.

It might (or might not, I'm not sure) be more efficient to draw the Video to a Canvas without a shader. and then draw the Canvas to the screen (or to another Canvas) using your shader, rather than calling VideoTexel a bunch of times per pixel.

[bartbes]

TexelVideo(texcoord)

VideoTexel