1 files changed, 83 insertions, 0 deletions
diff --git a/shaders/basic.frag b/shaders/basic.frag
new file mode 100644
index 0000000..4d7683c
--- /dev/null
+++ b/shaders/basic.frag
@@ -0,0 +1,83 @@
+#version 150
+#extension GL_ARB_explicit_attrib_location : enable
+#extension GL_ARB_explicit_uniform_location : enable
+
+layout(location = 0) out vec4 frag_color ;
+layout(location = 6) uniform vec4 lightPos ;
+
+layout(location = 8) uniform vec4 globalAmbient ;
+uniform float dX ;
+uniform float dY ;
+
+uniform mat4 mvMatrix ;
+uniform mat4 pjMatrix ;
+
+in vec3 normal ;
+
+uniform sampler2D textures[8] ;
+
+in float texture_blend[8] ;
+in vec2 texcoord ;
+in vec4 position ;
+
+vec3 sample(float xc,float yc) {
+    vec3 color = vec3(0);
+    for ( int i = 0 ; i < 8 ; ++ i ) {
+        vec4 tmp = texture2D(textures[i], texcoord + vec2(xc,yc)) ;
+        color += vec3(tmp) * texture_blend[i] ;
+    }
+    return color ;
+}
+
+vec3 sample2(int tex, float xc,float yc) {
+    vec3 color = vec3(0);
+    vec4 tmp = texture2D(textures[tex], texcoord + vec2(xc,yc)) ;
+    color += vec3(tmp) ;
+    return color ;
+}
+
+int dominentTexture() {
+    float m = 0.0 ;
+    int ret = 0;
+    for( int i = 0 ; i < 8 ; ++ i ) {
+        if( texture_blend [i] > m ) {
+            m = texture_blend[i] ;
+            ret = i ;
+        }
+    }
+    return ret ;
+}
+
+vec3 calNormChange( vec3 norm, vec3 down, vec3 right ) {
+    int dom = dominentTexture() ;
+    float x00 = length(sample2(dom,-dX, dY)); 
+    float x01 = length(sample2(dom,  0, dY)); 
+    float x02 = length(sample2(dom, dX, dY)); 
+
+    float x10 = length(sample2(dom,-dX, 0)); 
+    float x11 = length(sample2(dom,  0, 0)); 
+    float x12 = length(sample2(dom, dX, 0)); 
+
+    float x20 = length(sample2(dom,-dX,-dY)); 
+    float x21 = length(sample2(dom,  0,-dY)); 
+    float x22 = length(sample2(dom, dX,-dY)); 
+
+    down = ((x11 - x00) + (x11 - x01) + (x11 - x02) - (x11 - x20) - (x11 - x21) - (x11 - x22)) * down ;
+    right = ((x11 - x00) + (x11 - x10) + (x11 - x20) - (x11 - x02) - (x11 - x12) - (x11 - x22)) * right ;
+    
+    return (norm + down + right) / 3.0 ;
+}
+
+void main() {
+    vec3 down = vec3( 0.0, -1.0, 0.0 ) ;
+    vec3 right = normalize(cross( normal, down )) ;
+    down = normalize(cross( normal, right ) );
+    vec3 newNorm = calNormChange(normal,down,right) ;
+
+    vec3 color = sample(0,0) ;
+    
+    float prod = dot( normalize(-newNorm), normalize(vec3(lightPos - position)));
+    vec3 intensity = vec3(prod,prod,max(prod,0.4)) ;
+
+    frag_color = vec4(color * intensity,1) * vec4(normalize(globalAmbient.xyz),1.0);
+}