Complex Shader Life

ComplexShaderLife.txt

--# Main
displayMode(FULLSCREEN)

function setup()
    showBuffer = true
    readPixelCode = true
    local w,h = WIDTH,HEIGHT
    local w,h = 20,20
    source = image(w,h)
    target = image(w,h)
    worldEngine = mesh()
    local s = shader()
    s.vertexProgram, s.fragmentProgram = worldEngineShader()
    worldEngine.shader = s
    worldEngine.texture = source
    worldEngine:addRect(w/2,h/2,w,h)
    -- Factor of 2 is for retina displays
    worldEngine.shader.width = 2*w
    worldEngine.shader.height = 2*h
    worldEngine.shader.markerTurnA = true
    local leftOfVisible = color(0, 0, 25, 255)
    local belowLeftOfVisible = color(0,0,100,255)
    local belowVisible = color(0,0,150,255)
    local markerA = color(0, 0, 255, 255)
    local markerB = color(0, 255,255, 255)
    worldEngine.shader.leftOfVisible = leftOfVisible
    worldEngine.shader.belowLeftOfVisible = belowLeftOfVisible
    worldEngine.shader.belowVisible = belowVisible
    worldEngine.shader.markerA = markerA
    worldEngine.shader.markerB = markerB
    local nf = 50 + 5*math.random()
    local xd = math.random()
    local yd = math.random()
    for x = 1,w do
        for y = 1,h do
            if math.fmod(y,2) == 0 and math.fmod(x,2) == 1 then
                source:set(x,y,color(10,255,0,255)) -- color for ground
            elseif math.fmod(y,2) == 0 and math.fmod(x,2) == 0 then
                source:set(x,y,leftOfVisible)
            elseif math.fmod(y,2) == 1 and math.fmod(x,2) == 1 then
                source:set(x,y,belowVisible)
            elseif math.fmod(y,2) == 1 and math.fmod(x,2) == 0 then
                source:set(x,y,belowLeftOfVisible)
            end
            if math.fmod(y,8) == 0 and math.fmod(x,12) == 0 then
                source:set(x,y,markerA) -- color for initial creatures
            elseif (y == 2 or y == 18) and math.fmod(x,16) == 0 then
                source:set(x,y,markerB) -- color for initial creatures
            end
        end
    end
    visibleWorld = mesh()
    visibleWorld:addRect(WIDTH/2,HEIGHT/2,WIDTH,HEIGHT)
    s = shader()
    s.vertexProgram, s.fragmentProgram = displayShader()
    visibleWorld.shader = s
    visibleWorld.texture = source
    visibleWorld.shader.colour = color(36, 45, 69, 255)
    visibleWorld.shader.alive = color(30, 164, 23, 255)
    visibleWorld:setColors(255,255,255,255)
    visibleWorld.shader.width = worldEngine.shader.width
    visibleWorld.shader.height = worldEngine.shader.height
end

function draw() 
    background(56, 62, 61, 255)
    noSmooth()
    setContext(target)
    worldEngine:draw()
    setContext()
    source, target = target, source
    worldEngine.texture = source
    visibleWorld.texture = source
    visibleWorld:draw()
    if showBuffer then
        ortho()
        viewMatrix(matrix())
        sprite(target,170,170,320,320)
    end
    if worldEngine.shader.markerTurnA == true then
        worldEngine.shader.markerTurnA = false
    else
        worldEngine.shader.markerTurnA = true
    end
end

function touched(touch)
end
--# golShader
function worldEngineShader()
    return [[
//
// A Game of Life shader, vertex section does almost nothing.
//

//This is the current model * view * projection matrix
// Codea sets it automatically
uniform mat4 modelViewProjection;

//This is the current mesh vertex position, color and tex coord
// Set automatically
attribute vec4 position;
attribute vec4 color;
attribute vec2 texCoord;

//This is an output variable that will be passed to the fragment shader
varying lowp vec4 vColor;
varying highp vec2 vTexCoord;

void main()
{
    //Pass the everything to the fragment shader
    vColor = color;
    vTexCoord = texCoord;
    gl_Position = modelViewProjection * position;
}
]],
[[
// fragment shader, does the work.
    
//boilerplate:

//This represents the current texture on the mesh
uniform lowp sampler2D texture;

//The interpolated vertex color for this fragment
varying lowp vec4 vColor;

//The interpolated texture coordinate for this fragment
varying highp vec2 vTexCoord;

//custom code:

// width and height of the texture for finding neighbours
uniform highp float width;
uniform highp float height;
lowp float colstep = .05;
highp float w = 1./width;
highp float h = 1./height;   
uniform bool markerTurnA;
uniform highp vec4 leftOfVisible;
uniform highp vec4 belowLeftOfVisible;
uniform highp vec4 belowVisible;
uniform highp vec4 markerA;
uniform highp vec4 markerB;
highp vec2 above2 = vec2(0.,-4.);
highp vec2 aboveright2 = vec2(4.,-4.);
highp vec2 right2 = vec2(4.,0.);
highp vec2 belowright2 = vec2(4.,4.);
highp vec2 below2 = vec2(0.,4.);
highp vec2 belowleft2 = vec2(-4.,4.);
highp vec2 left2 = vec2(-4.,0.);
highp vec2 aboveleft2 = vec2(-4.,-4.);

//something mathy by Andrew Stacey, not sure what it does:
highp vec2 vfract(highp vec2 v) {
    return vec2(fract(v.x),fract(v.y)); //fract(whatever) returns just the decimal part?
}
    
// get the color in vector direction
lowp vec4 colorAt(highp vec2 direction) {
    lowp vec4 found = texture2D(texture,vfract(vTexCoord + vec2(w*direction.x,h*direction.y)));
    return found;
}
    
//check for markers
lowp vec2 markerInRadius () {
    highp vec4 thisColor =  colorAt(above2);
    if (thisColor == markerB || thisColor == markerA) {
        return above2;
    }
    thisColor =  colorAt(aboveright2);
    if (thisColor == markerB || thisColor == markerA) {
        return aboveright2;
    }
    thisColor =  colorAt(right2);
    if (thisColor == markerB || thisColor == markerA) {
        return right2;
    }    
    thisColor =  colorAt(belowright2);
    if (thisColor == markerB || thisColor == markerA) {
        return belowright2;
    }
    thisColor =  colorAt(below2);
    if (thisColor == markerB || thisColor == markerA) {
        return below2;
    }
    thisColor =  colorAt(belowleft2);
    if (thisColor == markerB || thisColor == markerA) {
        return belowleft2;
    }
    thisColor =  colorAt(left2);
    if (thisColor == markerB || thisColor == markerA) {
        return left2;
    }
    thisColor =  colorAt(aboveleft2);
    if (thisColor == markerB || thisColor == markerA) {
        //return aboveleft2;
    }
    return vec2(0.,0.);
}
   
void main()
{
    lowp vec4 col;
    col = texture2D(texture,vTexCoord);
    
    //colors defined
    lowp vec4 ground = vec4(0.04,1.,0.,1.);
    lowp vec4 livingThing = vec4(1.,0.,0.,1.);
    lowp vec4 colorToLeft = colorAt(vec2(-2.,0.)); 
    lowp vec4 colorTwoToLeft = colorAt(vec2(-4.,0.));
    
    //check if there is a marker around
    lowp vec2 markerAt = markerInRadius();
    if (markerAt != vec2(0.,0.)) {
        //get the color
        lowp vec4 colorThere = colorAt(markerAt);
        //if the position is to the left
        if (markerAt == left2) {
            //if it is a markerA on markerTurnA
            if (colorThere == markerA && markerTurnA == true) {
                //make this a markerB
                col = markerB;
            }
        //else if the position is up and left
        } else if (markerAt == belowleft2){
            //if it is a markerB NOT on markerTurnA
            if (colorThere == markerB && markerTurnA == false) {
                //make this a markerA
                col = markerA;
            }
        }
    }
    
    if (markerTurnA == true && col == markerA){
        col = leftOfVisible;
    } else if (markerTurnA == false && col == markerB){
        col = leftOfVisible;
    } else if (colorAt(vec2(-2.,0.)) == markerB || colorAt(vec2(-2.,0.)) == markerA){
        col =  livingThing;
    } else if (col == livingThing){
        col = ground;
    }

    
    //if this is markerTurnA...
    if (true ==false){
    if (markerTurnA == true){
        //if the color two to the left is markerA...
        if (colorTwoToLeft == markerA) {
            //make this markerB
           col = markerB;
        //but if the color one to the left is markerA...
        } else if (colorToLeft == markerA) {
            //this should be alive
            col = livingThing;
        //but if it is already alive..
        } else if (col == livingThing){
            //un-alive it
            col = ground;
        //but if this itself is markerA...
        } else if (col == markerA){
            //code it as the leftOfVisible
            col = leftOfVisible;
        }
    } else {  
        //if the color two to the left is markerB...
        if (colorTwoToLeft == markerB) {
            //make this markerA
            col = markerA;
        //but if the color one to the left is markerB...
        } else if (colorToLeft == markerB) {
            //this should be alive
            col = livingThing;
        //but if it is already alive..
        } else if (col == livingThing){
            //un-alive it
            col = ground;
        //but if this itself is markerB...
        } else if (col == markerB){
            //code it as the leftOfVisible
            col = leftOfVisible;
        }
    }
    }
    //Set the output color to the texture color
    gl_FragColor = col;
}
]]
end
--# golrShader
function displayShader()
    return [[
//
// Rendering vertex shader, does almost nothing.
//

//This is the current model * view * projection matrix
// Codea sets it automatically
uniform mat4 modelViewProjection;

//This is the current mesh vertex position, color and tex coord
// Set automatically
attribute vec4 position;
attribute vec4 color;
attribute vec2 texCoord;

//This is an output variable that will be passed to the fragment shader
varying lowp vec4 vColor;
varying highp vec2 vTexCoord;

void main()
{
    //Pass the everything to the fragment shader
    vColor = color;
    vTexCoord = texCoord;
    gl_Position = modelViewProjection * position;
}
]],[[
//
// Rendering fragment shader, interprets the raw GoL data.
//

//This is the raw data
uniform lowp sampler2D texture;

//Colours for rendering
uniform lowp vec4 colour;
uniform lowp vec4 alive;

//The interpolated vertex color for this fragment
varying lowp vec4 vColor;

//The interpolated texture coordinate for this fragment
varying highp vec2 vTexCoord;
    
// width and height of the texture for finding neighbours
uniform highp float width;
uniform highp float height;
lowp float colstep = .05;
highp float w = 1./width;
highp float h = 1./height;

highp vec2 vfract(highp vec2 v)
{
    return vec2(fract(v.x),fract(v.y)); //fract(whatever) returns just the decimal part?
}
    
// get the color in vector direction
lowp vec4 colorAt(highp vec2 direction)
{
    lowp vec4 found = texture2D(texture,vfract(vTexCoord + vec2(w*direction.x,h*direction.y)));
    return found;
}

void main()
{
    //Sample the data at the interpolated coordinate
    lowp vec4 col;
    col = texture2D( texture, vTexCoord );
    
    lowp float multiple = 80.;
    
    lowp vec4 rightColor = colorAt(vec2(multiple*w,0.));
    lowp vec4 upColor = colorAt(vec2(0.,multiple*h));
    lowp vec4 upAndRightColor = colorAt(vec2(multiple*w,multiple*h));
    if (col.r > 0.02) {
        //leave as is
    } else if (rightColor.r > 0.02 ){
        col = rightColor;
    } else if (upColor.r > 0.02) {
        col = upColor;
    } else if (upAndRightColor.r > 0.02) {
        col = upAndRightColor;
    }
    
    //Set the output color
    gl_FragColor = col;
}
]]
end