[orx-fx] Add DirectionalBlur

orx-fx/src/shaders/glsl/blur/directional-blur.frag

@@ -0,0 +1,67 @@
+#ifdef OR_IN_OUT
+in vec2 v_texCoord0;
+#else
+varying vec2 v_texCoord0;
+#endif
+
+uniform sampler2D tex0; // image
+uniform sampler2D tex1; // blurDirection
+uniform vec2 textureSize0;
+
+uniform int window;
+uniform float sigma;
+uniform float gain;
+uniform vec4 subtract;
+uniform float spread;
+
+uniform bool wrapX;
+uniform bool wrapY;
+uniform bool perpendicular;
+
+
+#ifndef OR_GL_FRAGCOLOR
+out vec4 o_color;
+#endif
+
+vec2 wrap(vec2 uv) {
+    vec2 res = uv;
+    if (wrapX) {
+        res.x = mod(res.x, 1.0);
+    }
+    if (wrapY) {
+        res.y = mod(res.y, 1.0);
+    }
+    return res;
+
+}
+void main() {
+    vec2 s = textureSize0;
+    s = vec2(1.0 / s.x, 1.0 / s.y);
+
+
+    vec4 sum = vec4(0.0, 0.0, 0.0, 0.0);
+    #ifndef OR_GL_TEXTURE2D
+    vec2 blurDirection = texture(tex1, v_texCoord0).xy;
+    if (perpendicular) {
+        blurDirection = vec2(-blurDirection.y, blurDirection.x);
+    }
+    float weight = 0.0;
+    for (int x = 0; x < window; ++x) {
+        sum += texture(tex0, wrap(v_texCoord0 + float(x) * blurDirection * s * spread));
+        weight += 1.0;
+    }
+    #else
+    vec2 blurDirection = texture2D(tex1, v_texCoord0);
+    float weight = 0.0;
+        sum += texture2D(tex0, wrap(v_texCoord0 * blurDirection * s * spread));
+
+    #endif
+
+
+    vec4 result = (sum/weight) * gain;
+    #ifdef OR_GL_FRAGCOLOR
+    gl_FragColor = result;
+    #else
+    o_color = result;
+    #endif
+}