Added FXAA example

This commit is contained in:
codeanticode
2012-05-27 01:37:57 +00:00
parent b1cecf494f
commit d2e4195c9a
2 changed files with 123 additions and 0 deletions

View File

@@ -0,0 +1,54 @@
// This example uses a FxAA post-processing filter for fast
// fullscreen antialiasing:
// http://www.kotaku.com.au/2011/12/what-is-fxaa/
//
// Press any key to enable/disable the shader.
PGraphics canvas;
PGraphicsOpenGL pg;
PShader shader;
boolean usingShader;
void setup() {
size(1280, 800, P2D);
noSmooth();
canvas = createGraphics(width, height, P2D);
canvas.noSmooth();
pg = (PGraphicsOpenGL) g;
shader = pg.loadShader("fxaa.glsl", POLY_SHADER_TEX);
pg.setShader(shader, POLY_SHADER_TEX);
println("FXAA shader is enabled");
usingShader = true;
canvas.beginDraw();
canvas.background(255);
canvas.stroke(0);
canvas.strokeWeight(15);
canvas.strokeCap(ROUND);
canvas.endDraw();
}
public void draw() {
canvas.beginDraw();
if (1 < dist(mouseX, mouseY, pmouseX, pmouseY)) {
canvas.line(pmouseX, pmouseY, mouseX, mouseY);
}
canvas.endDraw();
image(canvas, 0, 0);
}
public void keyPressed() {
if (usingShader) {
pg.defaultShader(POLY_SHADER_TEX);
println("FXAA shader is disabled");
usingShader = false;
} else {
pg.setShader(shader, POLY_SHADER_TEX);
println("FXAA shader is enabled");
usingShader = true;
}
}

View File

@@ -0,0 +1,69 @@
// FXAA shader, GLSL code adapted from:
// http://horde3d.org/wiki/index.php5?title=Shading_Technique_-_FXAA
// Whitepaper describing the technique:
// http://developer.download.nvidia.com/assets/gamedev/files/sdk/11/FXAA_WhitePaper.pdf
#ifdef GL_ES
precision mediump float;
precision mediump int;
#endif
uniform sampler2D textureSampler;
// The inverse of the texture dimensions along X and Y
uniform vec2 texcoordOffset;
varying vec4 vertColor;
varying vec4 vertTexcoord;
void main() {
// The parameters are hardcoded for now, but could be
// made into uniforms to control fromt he program.
float FXAA_SPAN_MAX = 8.0;
float FXAA_REDUCE_MUL = 1.0/8.0;
float FXAA_REDUCE_MIN = (1.0/128.0);
vec3 rgbNW = texture2D(textureSampler, vertTexcoord.xy + (vec2(-1.0, -1.0) * texcoordOffset)).xyz;
vec3 rgbNE = texture2D(textureSampler, vertTexcoord.xy + (vec2(+1.0, -1.0) * texcoordOffset)).xyz;
vec3 rgbSW = texture2D(textureSampler, vertTexcoord.xy + (vec2(-1.0, +1.0) * texcoordOffset)).xyz;
vec3 rgbSE = texture2D(textureSampler, vertTexcoord.xy + (vec2(+1.0, +1.0) * texcoordOffset)).xyz;
vec3 rgbM = texture2D(textureSampler, vertTexcoord.xy).xyz;
vec3 luma = vec3(0.299, 0.587, 0.114);
float lumaNW = dot(rgbNW, luma);
float lumaNE = dot(rgbNE, luma);
float lumaSW = dot(rgbSW, luma);
float lumaSE = dot(rgbSE, luma);
float lumaM = dot( rgbM, luma);
float lumaMin = min(lumaM, min(min(lumaNW, lumaNE), min(lumaSW, lumaSE)));
float lumaMax = max(lumaM, max(max(lumaNW, lumaNE), max(lumaSW, lumaSE)));
vec2 dir;
dir.x = -((lumaNW + lumaNE) - (lumaSW + lumaSE));
dir.y = ((lumaNW + lumaSW) - (lumaNE + lumaSE));
float dirReduce = max((lumaNW + lumaNE + lumaSW + lumaSE) * (0.25 * FXAA_REDUCE_MUL), FXAA_REDUCE_MIN);
float rcpDirMin = 1.0/(min(abs(dir.x), abs(dir.y)) + dirReduce);
dir = min(vec2(FXAA_SPAN_MAX, FXAA_SPAN_MAX),
max(vec2(-FXAA_SPAN_MAX, -FXAA_SPAN_MAX), dir * rcpDirMin)) * texcoordOffset;
vec3 rgbA = (1.0/2.0) * (
texture2D(textureSampler, vertTexcoord.xy + dir * (1.0/3.0 - 0.5)).xyz +
texture2D(textureSampler, vertTexcoord.xy + dir * (2.0/3.0 - 0.5)).xyz);
vec3 rgbB = rgbA * (1.0/2.0) + (1.0/4.0) * (
texture2D(textureSampler, vertTexcoord.xy + dir * (0.0/3.0 - 0.5)).xyz +
texture2D(textureSampler, vertTexcoord.xy + dir * (3.0/3.0 - 0.5)).xyz);
float lumaB = dot(rgbB, luma);
if((lumaB < lumaMin) || (lumaB > lumaMax)){
gl_FragColor.xyz=rgbA;
} else {
gl_FragColor.xyz=rgbB;
}
gl_FragColor.a = 1.0;
gl_FragColor *= vertColor;
}