PrusaSlicer-NonPlainar/resources/shaders/140/gouraud_light_instanced.vs

51 lines
1.9 KiB
GLSL

#version 140
#define INTENSITY_CORRECTION 0.6
// normalized values for (-0.6/1.31, 0.6/1.31, 1./1.31)
const vec3 LIGHT_TOP_DIR = vec3(-0.4574957, 0.4574957, 0.7624929);
#define LIGHT_TOP_DIFFUSE (0.8 * INTENSITY_CORRECTION)
#define LIGHT_TOP_SPECULAR (0.125 * INTENSITY_CORRECTION)
#define LIGHT_TOP_SHININESS 20.0
// normalized values for (1./1.43, 0.2/1.43, 1./1.43)
const vec3 LIGHT_FRONT_DIR = vec3(0.6985074, 0.1397015, 0.6985074);
#define LIGHT_FRONT_DIFFUSE (0.3 * INTENSITY_CORRECTION)
#define INTENSITY_AMBIENT 0.3
uniform mat4 view_model_matrix;
uniform mat4 projection_matrix;
uniform mat3 normal_matrix;
// vertex attributes
in vec3 v_position;
in vec3 v_normal;
// instance attributes
in vec3 i_offset;
in vec2 i_scales;
// x = tainted, y = specular;
out vec2 intensity;
void main()
{
// First transform the normal into camera space and normalize the result.
vec3 eye_normal = normalize(normal_matrix * v_normal);
// Compute the cos of the angle between the normal and lights direction. The light is directional so the direction is constant for every vertex.
// Since these two are normalized the cosine is the dot product. We also need to clamp the result to the [0,1] range.
float NdotL = max(dot(eye_normal, LIGHT_TOP_DIR), 0.0);
intensity.x = INTENSITY_AMBIENT + NdotL * LIGHT_TOP_DIFFUSE;
vec4 world_position = vec4(v_position * vec3(vec2(1.5 * i_scales.x), 1.5 * i_scales.y) + i_offset - vec3(0.0, 0.0, 0.5 * i_scales.y), 1.0);
vec4 eye_position = view_model_matrix * world_position;
intensity.y = LIGHT_TOP_SPECULAR * pow(max(dot(-normalize(eye_position.xyz), reflect(-LIGHT_TOP_DIR, eye_normal)), 0.0), LIGHT_TOP_SHININESS);
// Perform the same lighting calculation for the 2nd light source (no specular applied).
NdotL = max(dot(eye_normal, LIGHT_FRONT_DIR), 0.0);
intensity.x += NdotL * LIGHT_FRONT_DIFFUSE;
gl_Position = projection_matrix * eye_position;
}