Support gradient Cycles texture in GLSL viewport

source/blender/gpu/shaders/gpu_shader_material.glsl

@@ -2587,10 +2587,49 @@ void node_tex_coord_background(vec3 I, vec3 N, mat4 viewinvmat, mat4 obinvmat, v
 
 /* textures */
 
-void node_tex_gradient(vec3 co, out vec4 color, out float fac)
+float calc_gradient(vec3 p, int gradient_type)
+{
+	float x, y, z;
+	x = p.x;
+	y = p.y;
+	z = p.z;
+	if(gradient_type == 0) {  /* linear */
+		return x;
+	}
+	else if(gradient_type == 1) {  /* quadratic */
+		float r = max(x, 0.0);
+		return r*r;
+	}
+	else if(gradient_type == 2) {  /* easing */
+		float r = min(max(x, 0.0), 1.0);
+		float t = r*r;
+		return (3.0*t - 2.0*t*r);
+	}
+	else if(gradient_type == 3) {  /* diagonal */
+		return (x + y) * 0.5;
+	}
+	else if(gradient_type == 4) {  /* radial */
+		return atan(y, x) / (M_PI * 2) + 0.5;
+	}
+	else {
+		float r = max(1.0 - sqrt(x*x + y*y + z*z), 0.0);
+		if(gradient_type == 5) {  /* quadratic sphere */
+			return r*r;
+		}
+		else if(gradient_type == 6) {  /* sphere */
+			return r;
+		}
+	}
+	return 0.0;
+}
+
+void node_tex_gradient(vec3 co, float gradient_type, out vec4 color, out float fac)
 {
-	color = vec4(1.0);
-	fac = 1.0;
+	float f = calc_gradient(co, int(gradient_type));
+	f = clamp(f, 0.0, 1.0);
+
+	color = vec4(f, f, f, 1.0);
+	fac = f;
 }
 
 void node_tex_checker(vec3 co, vec4 color1, vec4 color2, float scale, out vec4 color, out float fac)

source/blender/nodes/shader/nodes/node_shader_tex_gradient.c

@@ -52,12 +52,16 @@ static void node_shader_init_tex_gradient(bNodeTree *UNUSED(ntree), bNode *node)
 
 static int node_shader_gpu_tex_gradient(GPUMaterial *mat, bNode *node, bNodeExecData *UNUSED(execdata), GPUNodeStack *in, GPUNodeStack *out)
 {
-	if (!in[0].link)
+	if (!in[0].link) {
 		in[0].link = GPU_attribute(CD_ORCO, "");
+		GPU_link(mat, "generated_from_orco", in[0].link, &in[0].link);
+	}
 
 	node_shader_gpu_tex_mapping(mat, node, in, out);
 
-	return GPU_stack_link(mat, "node_tex_gradient", in, out);
+	NodeTexGradient *tex = (NodeTexGradient *)node->storage;
+	float gradient_type = tex->gradient_type;
+	return GPU_stack_link(mat, "node_tex_gradient", in, out, GPU_uniform(&gradient_type));
 }
 
 /* node type definition */