grid = CreateObjectPlane(1.0, 1.0)
SetObjectTransparency(grid, 1)
SetObjectImage(grid, grid_img, 0)
SetObjectRotation(grid, 90.0, 0.0, 0.0)
SetObjectScale(grid, 5.0, 5.0, 1.0)
grid_shader = LoadShader("grid.vs", "grid.ps")
SetObjectShader(grid, grid_shader)
SetObjectShaderConstantByName(grid, "Scale", 5.0, 5.0, 0.0, 0.0)

attribute highp vec3 position;
attribute mediump vec3 normal;

varying highp vec3 posVarying;
varying mediump vec3 normalVarying;
varying mediump vec3 lightVarying;

mediump vec3 GetVSLighting( mediump vec3 normal, highp vec3 pos );

uniform highp mat3 agk_WorldNormal;
uniform highp mat4 agk_World;
uniform highp mat4 agk_ViewProj;

attribute highp vec2 uv;
varying highp vec2 uvVarying;
uniform highp vec4 uvBounds0;

void main()
{ 

	uvVarying = uv * uvBounds0.xy + uvBounds0.zw;
	highp vec4 pos = agk_World * vec4(position,1.0);
	gl_Position = agk_ViewProj * pos;
	mediump vec3 norm = normalize(agk_WorldNormal * normal);
	posVarying = pos.xyz;
	normalVarying = norm;
	lightVarying = GetVSLighting( norm, posVarying );

}

bool onGridline(int distFrom, int spacing);
bool onSplitline(int distFrom, int spacing, int interval);
varying mediump vec2 uvVarying;
uniform highp vec2 Scale;
 
uniform sampler2D texture0;
  
varying highp vec3 posVarying;
varying mediump vec3 normalVarying;
 
varying mediump vec3 lightVarying;
  
mediump vec3 GetPSLighting( mediump vec3 normal, highp vec3 pos );
mediump vec3 ApplyFog( mediump vec3 color, highp vec3 pointPos );
  
 
 
 
void main( )
{
 
 
    mediump vec3 norm = normalize(normalVarying);
    mediump vec3 light = lightVarying + GetPSLighting( norm, posVarying ); 
     
    mediump vec3 color = texture2D(texture0, uvVarying).rgb * light;
    color = ApplyFog( color, posVarying );
     
    gl_FragColor = vec4(color,1.0);
 
    // Colours , used to return to fragColor depending on criteria.
    const vec4 cBackground = vec4(0.0,0.0,0.0,0.0);         // Background colour.
    const vec4 cOrigin = vec4(0.0,0.392,0.392,1.0);         // Frag is directly in line with mouse's X or Y.
    const vec4 cLargeSplit = vec4(0.392,0.18,0.004,1.0);    // Frag is on a large split line.
    const vec4 cMedSplit = vec4(0.449,0.449,0.449,1.0);     // Frag is on a medium split line.
    const vec4 cGridline = vec4(0.293,0.293,0.293,1.0);     // Frag is on a grid line.
     
    // Grid lines
    const int spacingStd = 10;          // Spacing of normal grid lines
    const int intervalLargeSplit = 10;  // On how many gridlines a large split occurs.
    const int intervalMedSplit = 5;     // On how many gridlines a medium split occurs.
    const float zoom = 1.0;         // Zoom level of the grid.
     
    // Effective spacing
    // This is the standard grid spacing, as an integer, once zoom has been applied.
    // We do this here and use this value later to avoid float rounding errors.
    int effGrid = int(floor((float(spacingStd) * zoom) + 0.2));
     
    // Convenience integer values for resolution and frag position.
    int fragX = int((uvVarying.x-0.5)*Scale.x*10.0+(uvVarying.x-0.5));
    int fragY = int((uvVarying.y-0.5)*Scale.y*10.0+(uvVarying.y-0.5));
 
     
    // The offsets to the original mouse position were found by trial and error.
    int mouseX = 0;
    int mouseY = 0;
     
    // Distance this frag is from the mouse position, in each axis.
    int xDistFrom = int(abs(float(mouseX - fragX)));
    int yDistFrom = int(abs(float(mouseY - fragY)));
     
    // ============================================================
     
    // If on same X or Y as mouse, paint with origin colour.
    if ( fragX == mouseX || fragY == mouseY )
    {
        gl_FragColor = gl_FragColor*cOrigin;
        return;
    }
     
    // If on grid line, decide which colour to paint.
    else if ( onGridline(xDistFrom, effGrid) || onGridline(yDistFrom, effGrid) )
    {
        // If on large split line, choose this first.
        if ( onSplitline(xDistFrom, effGrid, intervalLargeSplit) ||
             onSplitline(yDistFrom, effGrid, intervalLargeSplit))
        {
            gl_FragColor = gl_FragColor*cLargeSplit;
            return;
        }
         
        // Then check medium split line.
        else if ( onSplitline(xDistFrom, effGrid, intervalMedSplit) ||
             onSplitline(yDistFrom, effGrid, intervalMedSplit))
        {
            gl_FragColor = gl_FragColor*cMedSplit;
            return;
        }
         
        // Otherwise, return normal grid line colour.
        else
        {
            gl_FragColor = gl_FragColor*cGridline;
            return;
        }
    }
     
    // Fragment is not in line with any grid line - paint as background.
    gl_FragColor = gl_FragColor*vec4(0.0, 0.0, 0.0, 0.0);
}
 
 
bool onGridline(int distFrom, int spacing)
{
    return mod(float(distFrom), float(spacing)) == 0.0;
}
 
 
bool onSplitline(int distFrom, int spacing, int interval)
{
    int newSpacing = spacing * interval;
     
    return mod(float(distFrom), float(newSpacing)) == 0.0;
}

uniform sampler2D texture0;
 
void main()
{
    vec4 basecolor = texture2D(texture0, uvVarying);
     
    //-- alpha blend
	if (overcolor.r > 0.0) {
		basecolor.r--;
	}

	if (overcolor.g > 0.0) {
		basecolor.g--;
	}

	if (overcolor.b > 0.0) {
		basecolor.b--;
	}
	
    //-- minus to erase
    gl_FragColor = basecolor;
      
     
}

uniform sampler2D texture0;

varying mediump vec2 uvVarying;

void main()
{
    vec4 color = texture2D(texture0, uvVarying).rgb;
    color -= vec4(1.0/255.0); // (no branching) make 255 steps as the color in shaders go from 0 to 1
    color = clamp(color,0.0,1.0);
    gl_FragColor = color; 
}

SetWindowSize( 1024, 768, 0 )
SetVirtualResolution( 1024, 768 )
 
LoadImage(1,"texture1.jpg") 

createShader()
CreateSprite(1,1)
LoadSpriteShader(1, "dissolve.ps")
SetSpriteShader( 1,1 )
resetTimer()
time#=Timer() 
do
	if Timer()>time#+1.5 
		resetTimer():time#=Timer()
	endif
	print (timer())
	sync()	

loop
 
function createShader()

file = OpenToWrite("dissolve.ps")
WriteLine(file,"uniform sampler2D texture0;")
WriteLine(file,"uniform float agk_time;")
WriteLine(file,"varying mediump vec2 uvVarying;")
WriteLine(file,"void main()")
WriteLine(file,"{")
WriteLine(file,"vec4 color = texture2D(texture0, uvVarying).rgba;")
WriteLine(file,"if (agk_time>1.0){")
WriteLine(file,"color=color-vec4(100.0/255.0);") // (no branching) make 255 steps as the color in shaders go from 0 to 1
WriteLine(file,"color = clamp(color,0.0,1.0);")
WriteLine(file,"}")
WriteLine(file,"gl_FragColor = color;")
WriteLine(file,"}")
CloseFile(file)
endfunction

// Eraser shader from MATTY_H -AGK forum
// texture

uniform sampler2D texture0;
varying vec2 uvVarying;
uniform float agk_time;
 
void main()
{
    vec4 color = texture2D(texture0, uvVarying);
    // color.r -= (1.0/255.0); // (no branching) make 255 steps as the color in shaders go from 0 to 1
    color.r -= agk_time;
    color.g -= agk_time;
	color.b -= agk_time;
    color = clamp(color,0.0,1.0);
    gl_FragColor = color; 
}

sprite = CreateSprite(LoadImage("image.jpg"))

SetSpriteShader(sprite, LoadSpriteShader("fade.ps" ) )

do
	if Timer() > 1.0
		ResetTimer()
	endif
	
    Print( ScreenFPS() )
    Sync()
loop

SetWindowSize( 1024, 768, 0 )
SetVirtualResolution( 1024, 768 )
 
LoadImage(1,"texture1.jpg") 

createShader()
CreateSprite(1,1)
LoadSpriteShader(1, "dissolve.ps")
SetSpriteShader( 1,1 )
resetTimer()
do
	time#=Timer()
        //SetShaderConstantByName(1,"myColor",-time#-,time#,-time#,0.2) //this will make the channels brighter
	SetShaderConstantByName(1,"myColor",time#,time#,time#,0.2) //red green blue factor
	if Timer()>7.0 
		resetTimer()
	endif
	print (time#)
	sync()	

loop
 
function createShader()

file = OpenToWrite("dissolve.ps")
WriteLine(file,"uniform sampler2D texture0;")
//WriteLine(file,"uniform float agk_time;")
WriteLine(file,"varying mediump vec2 uvVarying;")
WriteLine(file,"uniform vec4 myColor;")
WriteLine(file,"void main()")
WriteLine(file,"{")
WriteLine(file,"vec4 color = texture2D(texture0, uvVarying).rgba;")
WriteLine(file,"//color=color-vec4(100.0/255.0);") // (no branching) make 255 steps as the color in shaders go from 0 to 1
WriteLine(file,"color.r-=(myColor.x*myColor.w);")
WriteLine(file,"color.g-=(myColor.y*myColor.w);")
WriteLine(file,"color.b-=(myColor.z*myColor.w);")
WriteLine(file,"color = clamp(color,0.0,1.0);") //restricts color range
WriteLine(file,"gl_FragColor = color;")
WriteLine(file,"}")
CloseFile(file)
endfunction

time#=Timer()
	r#=time#*(255/255) //red (colors you want divided by 255) 
	g#=time#*(255/255) //green
	b#=time#*(0/255) //Blue        makes yellow    rgb (255,255,0)
	SetShaderConstantByName(1,"myColor",-r#,-g#,-b#,0.2) //red green blue factor

time#=7-Timer()
	r#=time#
	g#=time#
	b#=time#  
	if timer()<7.0
		SetShaderConstantByName(1,"myColor",r#,g#,b#,0.2) //red green blue factor
	endif