LÖVE

Code: Select all

uniform sampler2D tex0;
uniform int size;
uniform vec2 step;

void main(void)
{
    vec4 sample = vec4(0.0);
    vec2 uv = gl_TexCoord[0].st;
    float a = texture2D(tex0, uv).a;
    int hs = size / 2;

    // gaussian blur
    int i, k;
    for (i = -hs; i <= hs; i++) {
        for (k = -hs; k <= hs; k++) {
            sample += texture2D(tex0, uv + vec2( float(i) * step.x, float(k) * step.y ));
        }
    }

    sample /= float(size * size);
    sample.a = a;

    if (sample.r + sample.b + sample.g > 0.0)
        gl_FragColor = sample;
    else
        gl_FragColor = gl_Color;
}

Code: Select all

-- in love.load()
blur = love.graphics.newProgram()
blur:attachShader(
    love.graphics.newShader('vertex', love.filesystem.read("null.vs"))
    love.graphics.newShader('fragment', love.filesystem.read("blur.fs")))
blur:link()

blursize = 5
blur:uniform('size', 'int', blursize)
blur:uniform('step', 'float', 1 / love.graphics.getWidth(), 1 / love.graphics.getHeight())

--------------------
-- in love.draw()
blur:use()
-- draw stuff
blur:unuse()
-- draw hud

--------------------
-- in love.keypressed(key)
if key == "kp+" then
    blursize = blursize + 1
    blur:uniform('size', 'int', blursize)
elseif key == "kp-" then
    blursize = math.max(blursize  - 1, 1)
    blur:uniform('size', 'int', blursize)
end
print(blur:uniform('size', 'int'))

Code: Select all

uniform sampler2D tex0;
uniform sampler2D alphaMask;

void main(void)
{
    vec2 uv = gl_TexCoord[0].st;
    if (texture2D(alphaMask, uv).a > 0)
        gl_FragColor = texture2D(tex0, uv);
    else
        gl_FragColor = vec4(0.0);
}

Code: Select all

-- Initialization
function love.load()
	
	-- Load background picture.
	picture = love.graphics.newImage('picture.png')
	
	-- Load radial gradient image for hole.
	hole = love.graphics.newImage('hole.png')
	
	-- Create 100px size font.
	bigFont = love.graphics.newFont( 100 )
	
	-- Create the fbo object for the hole.
	hole_buffer = love.graphics.newFbo( love.graphics.getWidth(), love.graphics.getHeight() )
end

-- Logic
function love.update(dt)
end

function hole_render()
	local mx, my = love.mouse.getPosition()
	
	-- Set draw vars.
	-- Sets the blend mode to: glBlendFunc( GL_ZERO, GL_ONE_MINUS_SRC_ALPHA )
	love.graphics.setBlendMode('hole')
	love.graphics.setFont( bigFont )
	love.graphics.setColor( 255, 255, 255, 255 )
	
	-- Draw
	love.graphics.draw( hole, mx, my, 0, 1, 1, 100, 100 )
	love.graphics.print( 'hello world', 100, 300 )
	
	-- Draw frames per second.
	love.graphics.print( love.timer.getFPS(), 100, 20 )
end

-- Scene Drawing
function love.draw()

	-- Render into the hole buffer.
	hole_buffer:render( hole_render )
	
	-- Set draw vars.
	love.graphics.setColor(255,255,255,255)
	
	-- Draw the background picture
	love.graphics.draw( picture, 0, 0 )
	
	-- Draw the hole.
	love.graphics.draw( hole_buffer, 0, 0 )
	
end