Shader fixes (pulled across from Synth3D)

git-svn-id: svn://cook.msm.cam.ac.uk:745/diff-tomo/dtr@282 bf6ca9ba-c028-0410-8290-897cf20841d1

3 files changed, 47 insertions, 35 deletions

diff --git a/data/light-pp.frag b/data/light-pp.frag
index ca96990..c40b302 100644
--- a/data/light-pp.frag
+++ b/data/light-pp.frag
@@ -9,35 +9,44 @@
  *
  */
 
-varying vec4 col_ambi;
-varying vec4 col_diff;
-varying vec4 col_spec;
-varying vec4 col_emit;
+varying vec3 col_ambi;
+varying vec3 col_diff;
+varying vec3 col_spec;
+varying vec3 col_emit;
 varying float shininess;
 
 varying vec3 normal;
-varying vec3 halfvc;
+varying vec3 lightvc;
+varying vec3 lighthvc;
 
 void main() {
 	
-	vec4 ambi;
-	vec4 diff;
-	vec4 spec;
+	vec3 ambi;
+	vec3 emit;
+	vec3 diff;
+	vec3 spec;
+	
+	vec3 norm = normalize(normal);
 	
 	/* Ambient contribution */
-	ambi = col_ambi * gl_LightModel.ambient;
-	ambi += col_ambi * gl_LightSource[0].ambient;
+	ambi = col_ambi * gl_LightModel.ambient.rgb;
+	
+	/* Emission */
+	emit = col_emit;
 	
 	/* Diffuse contribution */
-	diff = col_diff * clamp(dot( vec3(normalize(gl_LightSource[0].position)), normal ), 0.0, 1.0);
+	diff = col_diff * gl_LightSource[0].diffuse.rgb * max(dot(normalize(lightvc).xyz, norm), 0.0);
 	
 	/* Specular contribution */
-	spec = col_spec * clamp(pow(dot( vec3(normal), halfvc ), shininess), 0.0, 1.0);
+	if ( col_spec.r > 0.0 ) {
+		float ndothv = max(dot(norm, normalize(lighthvc)), 0.0);
+		spec = col_spec * gl_LightSource[0].specular.rgb * pow(ndothv, shininess);
+	}
 	
-	gl_FragColor = vec4(min(col_emit.r + ambi.r + diff.r + spec.r, 1.0),
-			    min(col_emit.g + ambi.g + diff.g + spec.g, 1.0),
-			    min(col_emit.b + ambi.b + diff.b + spec.b, 1.0),
-			    min(col_emit.a + ambi.a + diff.a + spec.a, 1.0));
+	gl_FragColor = vec4(min(emit.r + ambi.r + diff.r + spec.r, 1.0),
+			    min(emit.g + ambi.g + diff.g + spec.g, 1.0),
+			    min(emit.b + ambi.b + diff.b + spec.b, 1.0),
+			    1.0);
 	
 }
 
diff --git a/data/light-pp.vert b/data/light-pp.vert
index d01f135..8333aae 100644
--- a/data/light-pp.vert
+++ b/data/light-pp.vert
@@ -9,25 +9,26 @@
  *
  */
 
-varying vec4 col_ambi;
-varying vec4 col_diff;
-varying vec4 col_spec;
-varying vec4 col_emit;
+varying vec3 col_ambi;
+varying vec3 col_diff;
+varying vec3 col_spec;
+varying vec3 col_emit;
 varying float shininess;
 
 varying vec3 normal;
-varying vec3 halfvc;
+varying vec3 lightvc;
+varying vec3 lighthvc;
 
 void main() {
 	
 	normal = normalize(gl_NormalMatrix * gl_Normal);
-	halfvc = vec3(gl_LightSource[0].halfVector);
-	
-	col_ambi = gl_FrontMaterial.ambient;
-	col_diff = gl_FrontMaterial.diffuse;
-	col_spec = gl_FrontMaterial.specular;
-	col_emit = gl_FrontMaterial.emission;
+	lightvc = normalize(vec3(gl_LightSource[0].position));
+	lighthvc = normalize(gl_LightSource[0].halfVector.xyz);
 	
+	col_ambi = gl_Color.rgb;
+	col_diff = gl_Color.rgb;
+	col_spec = gl_FrontMaterial.specular.rgb;
+	col_emit = gl_FrontMaterial.emission.rgb;
 	shininess = gl_FrontMaterial.shininess;
 	
 	gl_Position = ftransform();
diff --git a/src/glbits.c b/src/glbits.c
index aff3a36..b489ea6 100644
--- a/src/glbits.c
+++ b/src/glbits.c
@@ -651,10 +651,9 @@ gint glbits_expose(GtkWidget *widget, GdkEventExpose *event, DisplayWindow *dw)
 	float m[4][4];
 	GLfloat black[] = { 0.0, 0.0, 0.0, 1.0 };
 	GLfloat blue[] = { 0.0, 0.0, 0.5, 1.0 };
-	GLfloat blue_spec[] = { 0.0, 0.0, 1.0, 1.0 };
-	GLfloat gold[] = { 0.5, 0.5, 0.0, 1.0 };
-	GLfloat gold_spec[] = { 0.9, 0.9, 0.0, 1.0 };
-	GLfloat light0_position[] = { 0.1, 0.1, 1.0, 0.0 };
+	GLfloat white[] = { 1.0, 1.0, 1.0, 1.0 };
+	GLfloat gold[] = { 0.7, 0.7, 0.0, 1.0 };
+	GLfloat light0_position[] = { 0.0, 1.0, 1.0, 0.0 };
 	GLfloat light0_diffuse[]  = { 0.8, 0.8, 0.8, 1.0 };
 	GLfloat light0_specular[] = { 0.8, 0.8, 0.8, 1.0 };
 	GLfloat grey[] = { 0.6, 0.6, 0.6, 1.0 };
@@ -734,6 +733,7 @@ gint glbits_expose(GtkWidget *widget, GdkEventExpose *event, DisplayWindow *dw)
 			glMaterialfv(GL_FRONT_AND_BACK, GL_EMISSION, black);
 			glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, black);
 			glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, black);
+			glColor3f(0.0, 0.0, 0.0);
 			glMaterialf(GL_FRONT_AND_BACK, GL_SHININESS, 0.0);
 			
 			if ( dw->gl_use_buffers ) {
@@ -758,8 +758,9 @@ gint glbits_expose(GtkWidget *widget, GdkEventExpose *event, DisplayWindow *dw)
 		
 			glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, blue);
 			glMaterialfv(GL_FRONT_AND_BACK, GL_EMISSION, black);
-			glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, blue_spec);
-			glMaterialf(GL_FRONT_AND_BACK, GL_SHININESS, 50.0);
+			glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, white);
+			glMaterialf(GL_FRONT_AND_BACK, GL_SHININESS, 100.0);
+			glColor3f(0.0, 0.0, 1.0);
 			
 			if ( dw->gl_use_buffers ) {
 				glBindBufferARB(GL_ARRAY_BUFFER, dw->gl_marker_vertex_buffer);
@@ -783,8 +784,9 @@ gint glbits_expose(GtkWidget *widget, GdkEventExpose *event, DisplayWindow *dw)
 			
 			glMaterialfv(GL_FRONT_AND_BACK, GL_EMISSION, black);
 			glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, gold);
-			glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, gold_spec);
-			glMaterialf(GL_FRONT_AND_BACK, GL_SHININESS, 70.0);
+			glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, white);
+			glMaterialf(GL_FRONT_AND_BACK, GL_SHININESS, 100.0);
+			glColor3f(0.7, 0.7, 0.0);
 			
 			glUseProgramObjectARB(dw->gl_program_lightpp);
 			if ( dw->gl_use_buffers ) {