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[core] Re-generate shaders.

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This commit is contained in:
Chris Loer
2017-05-16 11:50:24 -07:00
committed by Ansis Brammanis
parent 8c23f14a9f
commit 7c7564d72e
3 changed files with 182 additions and 87 deletions
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36
src/mbgl/shaders/collision_box.cpp
View File

@@ -8,44 +8,74 @@ namespace shaders {
const char* collision_box::name = "collision_box";
const char* collision_box::vertexSource = R"MBGL_SHADER(
attribute vec2 a_pos;
attribute vec2 a_anchor_pos;
attribute vec2 a_extrude;
attribute vec2 a_data;
uniform mat4 u_matrix;
uniform float u_scale;
uniform float u_pitch;
uniform float u_collision_y_stretch;
uniform float u_camera_to_center_distance;
varying float v_max_zoom;
varying float v_placement_zoom;
varying float v_perspective_zoom_adjust;
varying vec2 v_fade_tex;
void main() {
gl_Position = u_matrix * vec4(a_pos + a_extrude / u_scale, 0.0, 1.0);
vec4 projectedPoint = u_matrix * vec4(a_anchor_pos, 0, 1);
highp float camera_to_anchor_distance = projectedPoint.w;
highp float collision_perspective_ratio = 1.0 + 0.5 * ((camera_to_anchor_distance / u_camera_to_center_distance) - 1.0);
highp float incidence_stretch = camera_to_anchor_distance / (u_camera_to_center_distance * cos(u_pitch));
highp float collision_adjustment = max(1.0, incidence_stretch / u_collision_y_stretch);
gl_Position = u_matrix * vec4(a_pos + a_extrude * collision_perspective_ratio * collision_adjustment / u_scale, 0.0, 1.0);
v_max_zoom = a_data.x;
v_placement_zoom = a_data.y;
v_perspective_zoom_adjust = log2(collision_perspective_ratio * collision_adjustment) * 10.0;
v_fade_tex = vec2((v_placement_zoom + v_perspective_zoom_adjust) / 255.0, 0.0);
}
)MBGL_SHADER";
const char* collision_box::fragmentSource = R"MBGL_SHADER(
uniform float u_zoom;
// u_maxzoom is derived from the maximum scale considered by the CollisionTile
// Labels with placement zoom greater than this value will not be placed,
// regardless of perspective effects.
uniform float u_maxzoom;
uniform sampler2D u_fadetexture;
// v_max_zoom is a collision-box-specific value that controls when line-following
// collision boxes are used.
varying float v_max_zoom;
varying float v_placement_zoom;
varying float v_perspective_zoom_adjust;
varying vec2 v_fade_tex;
void main() {
float alpha = 0.5;
// Green = no collisions, label is showing
gl_FragColor = vec4(0.0, 1.0, 0.0, 1.0) * alpha;
if (v_placement_zoom > u_zoom) {
// Red = collision, label hidden
if (texture2D(u_fadetexture, v_fade_tex).a < 1.0) {
gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0) * alpha;
}
if (u_zoom >= v_max_zoom) {
// Faded black = this collision box is not used at this zoom (for curved labels)
if (u_zoom >= v_max_zoom + v_perspective_zoom_adjust) {
gl_FragColor = vec4(0.0, 0.0, 0.0, 1.0) * alpha * 0.25;
}
// Faded blue = the placement scale for this label is beyond the CollisionTile
// max scale, so it's impossible for this label to show without collision detection
// being run again (the label's glyphs haven't even been added to the symbol bucket)
if (v_placement_zoom >= u_maxzoom) {
gl_FragColor = vec4(0.0, 0.0, 1.0, 1.0) * alpha * 0.2;
}

44
src/mbgl/shaders/symbol_icon.cpp
View File

@@ -7,17 +7,20 @@ namespace shaders {
const char* symbol_icon::name = "symbol_icon";
const char* symbol_icon::vertexSource = R"MBGL_SHADER(
attribute vec4 a_pos_offset;
attribute vec2 a_label_pos;
attribute vec4 a_data;
// icon-size data (see symbol_sdf.vertex.glsl for more)
attribute vec3 a_size;
uniform bool u_is_size_zoom_constant;
uniform bool u_is_size_feature_constant;
uniform mediump float u_size_t; // used to interpolate between zoom stops when size is a composite function
uniform mediump float u_size; // used when size is both zoom and feature constant
uniform mediump float u_layout_size; // used when size is feature constant
uniform highp float u_size_t; // used to interpolate between zoom stops when size is a composite function
uniform highp float u_size; // used when size is both zoom and feature constant
uniform highp float u_layout_size; // used when size is feature constant
uniform highp float u_camera_to_center_distance;
uniform highp float u_pitch;
uniform highp float u_collision_y_stretch;
#ifndef HAS_UNIFORM_u_opacity
@@ -32,7 +35,7 @@ uniform lowp float u_opacity;
uniform mat4 u_matrix;
uniform bool u_is_text;
uniform mediump float u_zoom;
uniform highp float u_zoom;
uniform bool u_rotate_with_map;
uniform vec2 u_extrude_scale;
@@ -53,11 +56,11 @@ void main() {
vec2 a_offset = a_pos_offset.zw;
vec2 a_tex = a_data.xy;
mediump vec2 label_data = unpack_float(a_data[2]);
mediump float a_labelminzoom = label_data[0];
mediump vec2 a_zoom = unpack_float(a_data[3]);
mediump float a_minzoom = a_zoom[0];
mediump float a_maxzoom = a_zoom[1];
highp vec2 label_data = unpack_float(a_data[2]);
highp float a_labelminzoom = label_data[0];
highp vec2 a_zoom = unpack_float(a_data[3]);
highp float a_minzoom = a_zoom[0];
highp float a_maxzoom = a_zoom[1];
float size;
// In order to accommodate placing labels around corners in
@@ -68,7 +71,7 @@ void main() {
// currently rendered zoom level if text-size is zoom-dependent.
// Thus, we compensate for this difference by calculating an adjustment
// based on the scale of rendered text size relative to layout text size.
mediump float layoutSize;
highp float layoutSize;
if (!u_is_size_zoom_constant && !u_is_size_feature_constant) {
size = mix(a_size[0], a_size[1], u_size_t) / 10.0;
layoutSize = a_size[2] / 10.0;
@@ -85,12 +88,16 @@ void main() {
float fontScale = u_is_text ? size / 24.0 : size;
mediump float zoomAdjust = log2(size / layoutSize);
mediump float adjustedZoom = (u_zoom - zoomAdjust) * 10.0;
highp float zoomAdjust = log2(size / layoutSize);
highp float adjustedZoom = (u_zoom - zoomAdjust) * 10.0;
// result: z = 0 if a_minzoom <= adjustedZoom < a_maxzoom, and 1 otherwise
mediump float z = 2.0 - step(a_minzoom, adjustedZoom) - (1.0 - step(a_maxzoom, adjustedZoom));
highp float z = 2.0 - step(a_minzoom, adjustedZoom) - (1.0 - step(a_maxzoom, adjustedZoom));
vec2 extrude = fontScale * u_extrude_scale * (a_offset / 64.0);
vec4 projectedPoint = u_matrix * vec4(a_label_pos, 0, 1);
highp float camera_to_anchor_distance = projectedPoint.w;
highp float perspective_ratio = 1.0 + 0.5*((camera_to_anchor_distance / u_camera_to_center_distance) - 1.0);
vec2 extrude = fontScale * u_extrude_scale * perspective_ratio * (a_offset / 64.0);
if (u_rotate_with_map) {
gl_Position = u_matrix * vec4(a_pos + extrude, 0, 1);
gl_Position.z += z * gl_Position.w;
@@ -99,7 +106,12 @@ void main() {
}
v_tex = a_tex / u_texsize;
v_fade_tex = vec2(a_labelminzoom / 255.0, 0.0);
// See comments in symbol_sdf.vertex
highp float incidence_stretch = camera_to_anchor_distance / (u_camera_to_center_distance * cos(u_pitch));
highp float collision_adjustment = max(1.0, incidence_stretch / u_collision_y_stretch);
highp float perspective_zoom_adjust = log2(perspective_ratio * collision_adjustment) * 10.0;
v_fade_tex = vec2((a_labelminzoom + perspective_zoom_adjust) / 255.0, 0.0);
}
)MBGL_SHADER";

189
src/mbgl/shaders/symbol_sdf.cpp
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@@ -9,7 +9,10 @@ const char* symbol_sdf::name = "symbol_sdf";
const char* symbol_sdf::vertexSource = R"MBGL_SHADER(
const float PI = 3.141592653589793;
// NOTE: the a_data attribute in this shader is manually bound (see https://github.com/mapbox/mapbox-gl-js/issues/4607).
// If removing or renaming a_data, revisit the manual binding in painter.js accordingly.
attribute vec4 a_pos_offset;
attribute vec2 a_label_pos;
attribute vec4 a_data;
// contents of a_size vary based on the type of property value
@@ -23,12 +26,12 @@ attribute vec4 a_data;
attribute vec3 a_size;
uniform bool u_is_size_zoom_constant;
uniform bool u_is_size_feature_constant;
uniform mediump float u_size_t; // used to interpolate between zoom stops when size is a composite function
uniform mediump float u_size; // used when size is both zoom and feature constant
uniform mediump float u_layout_size; // used when size is feature constant
uniform highp float u_size_t; // used to interpolate between zoom stops when size is a composite function
uniform highp float u_size; // used when size is both zoom and feature constant
uniform highp float u_layout_size; // used when size is feature constant
#ifndef HAS_UNIFORM_u_fill_color
#ifdef HAS_UNIFORM_u_fill_color
uniform lowp float a_fill_color_t;
attribute highp vec4 a_fill_color;
varying highp vec4 fill_color;
@@ -36,7 +39,8 @@ varying highp vec4 fill_color;
uniform highp vec4 u_fill_color;
#endif
#ifndef HAS_UNIFORM_u_halo_color
#ifdef HAS_UNIFORM_u_halo_color
uniform lowp float a_halo_color_t;
attribute highp vec4 a_halo_color;
varying highp vec4 halo_color;
@@ -44,7 +48,8 @@ varying highp vec4 halo_color;
uniform highp vec4 u_halo_color;
#endif
#ifndef HAS_UNIFORM_u_opacity
#ifdef HAS_UNIFORM_u_opacity
uniform lowp float a_opacity_t;
attribute lowp vec2 a_opacity;
varying lowp float opacity;
@@ -52,7 +57,8 @@ varying lowp float opacity;
uniform lowp float u_opacity;
#endif
#ifndef HAS_UNIFORM_u_halo_width
#ifdef HAS_UNIFORM_u_halo_width
uniform lowp float a_halo_width_t;
attribute lowp vec2 a_halo_width;
varying lowp float halo_width;
@@ -60,7 +66,8 @@ varying lowp float halo_width;
uniform lowp float u_halo_width;
#endif
#ifndef HAS_UNIFORM_u_halo_blur
#ifdef HAS_UNIFORM_u_halo_blur
uniform lowp float a_halo_blur_t;
attribute lowp vec2 a_halo_blur;
varying lowp float halo_blur;
@@ -68,68 +75,89 @@ varying lowp float halo_blur;
uniform lowp float u_halo_blur;
#endif
// matrix is for the vertex position.
uniform mat4 u_matrix;
uniform bool u_is_text;
uniform mediump float u_zoom;
uniform highp float u_zoom;
uniform bool u_rotate_with_map;
uniform bool u_pitch_with_map;
uniform mediump float u_pitch;
uniform mediump float u_bearing;
uniform mediump float u_aspect_ratio;
uniform highp float u_pitch;
uniform highp float u_bearing;
uniform highp float u_aspect_ratio;
uniform highp float u_camera_to_center_distance;
uniform highp float u_max_camera_distance;
uniform highp float u_collision_y_stretch;
uniform vec2 u_extrude_scale;
uniform vec2 u_texsize;
varying vec4 v_data0;
varying vec2 v_data1;
varying vec2 v_tex;
varying vec2 v_fade_tex;
varying float v_gamma_scale;
varying float v_size;
// Used below to move the vertex out of the clip space for when the current
// zoom is out of the glyph's zoom range.
highp float clipUnusedGlyphAngles(const highp float render_size,
const highp float layout_size,
const highp float min_zoom,
const highp float max_zoom) {
highp float zoom_adjust = log2(render_size / layout_size);
highp float adjusted_zoom = (u_zoom - zoom_adjust) * 10.0;
// result: 0 if min_zoom <= adjusted_zoom < max_zoom, and 1 otherwise
return 2.0 - step(min_zoom, adjusted_zoom) - (1.0 - step(max_zoom, adjusted_zoom));
}
void main() {
#ifndef HAS_UNIFORM_u_fill_color
fill_color = unpack_mix_vec4(a_fill_color, a_fill_color_t);
#else
highp vec4 fill_color = u_fill_color;
#endif
#ifndef HAS_UNIFORM_u_halo_color
halo_color = unpack_mix_vec4(a_halo_color, a_halo_color_t);
#else
highp vec4 halo_color = u_halo_color;
#endif
#ifndef HAS_UNIFORM_u_opacity
opacity = unpack_mix_vec2(a_opacity, a_opacity_t);
#else
lowp float opacity = u_opacity;
#endif
#ifndef HAS_UNIFORM_u_halo_width
halo_width = unpack_mix_vec2(a_halo_width, a_halo_width_t);
#else
lowp float halo_width = u_halo_width;
#endif
#ifndef HAS_UNIFORM_u_halo_blur
halo_blur = unpack_mix_vec2(a_halo_blur, a_halo_blur_t);
#else
lowp float halo_blur = u_halo_blur;
#endif
vec2 a_pos = a_pos_offset.xy;
vec2 a_offset = a_pos_offset.zw;
vec2 a_tex = a_data.xy;
mediump vec2 label_data = unpack_float(a_data[2]);
mediump float a_labelminzoom = label_data[0];
mediump float a_labelangle = label_data[1];
mediump vec2 a_zoom = unpack_float(a_data[3]);
mediump float a_minzoom = a_zoom[0];
mediump float a_maxzoom = a_zoom[1];
float size;
highp vec2 label_data = unpack_float(a_data[2]);
highp float a_labelminzoom = label_data[0];
highp float a_lineangle = (label_data[1] / 256.0 * 2.0 * PI);
highp vec2 a_zoom = unpack_float(a_data[3]);
highp float a_minzoom = a_zoom[0];
highp float a_maxzoom = a_zoom[1];
// In order to accommodate placing labels around corners in
// symbol-placement: line, each glyph in a label could have multiple
@@ -139,79 +167,97 @@ void main() {
// currently rendered zoom level if text-size is zoom-dependent.
// Thus, we compensate for this difference by calculating an adjustment
// based on the scale of rendered text size relative to layout text size.
mediump float layoutSize;
highp float layoutSize;
if (!u_is_size_zoom_constant && !u_is_size_feature_constant) {
size = mix(a_size[0], a_size[1], u_size_t) / 10.0;
v_size = mix(a_size[0], a_size[1], u_size_t) / 10.0;
layoutSize = a_size[2] / 10.0;
} else if (u_is_size_zoom_constant && !u_is_size_feature_constant) {
size = a_size[0] / 10.0;
layoutSize = size;
v_size = a_size[0] / 10.0;
layoutSize = v_size;
} else if (!u_is_size_zoom_constant && u_is_size_feature_constant) {
size = u_size;
v_size = u_size;
layoutSize = u_layout_size;
} else {
size = u_size;
v_size = u_size;
layoutSize = u_size;
}
float fontScale = u_is_text ? size / 24.0 : size;
float fontScale = u_is_text ? v_size / 24.0 : v_size;
mediump float zoomAdjust = log2(size / layoutSize);
mediump float adjustedZoom = (u_zoom - zoomAdjust) * 10.0;
// result: z = 0 if a_minzoom <= adjustedZoom < a_maxzoom, and 1 otherwise
// Used below to move the vertex out of the clip space for when the current
// zoom is out of the glyph's zoom range.
mediump float z = 2.0 - step(a_minzoom, adjustedZoom) - (1.0 - step(a_maxzoom, adjustedZoom));
vec4 projectedPoint = u_matrix * vec4(a_label_pos, 0, 1);
highp float camera_to_anchor_distance = projectedPoint.w;
highp float perspective_ratio = 1.0 + 0.5*((camera_to_anchor_distance / u_camera_to_center_distance) - 1.0);
// pitch-alignment: map
// rotation-alignment: map | viewport
if (u_pitch_with_map) {
lowp float angle = u_rotate_with_map ? (a_labelangle / 256.0 * 2.0 * PI) : u_bearing;
lowp float asin = sin(angle);
lowp float acos = cos(angle);
highp float angle = u_rotate_with_map ? a_lineangle : u_bearing;
highp float asin = sin(angle);
highp float acos = cos(angle);
mat2 RotationMatrix = mat2(acos, asin, -1.0 * asin, acos);
vec2 offset = RotationMatrix * a_offset;
vec2 extrude = fontScale * u_extrude_scale * (offset / 64.0);
vec2 extrude = fontScale * u_extrude_scale * perspective_ratio * (offset / 64.0);
gl_Position = u_matrix * vec4(a_pos + extrude, 0, 1);
gl_Position.z += z * gl_Position.w;
gl_Position.z += clipUnusedGlyphAngles(v_size*perspective_ratio, layoutSize, a_minzoom, a_maxzoom) * gl_Position.w;
// pitch-alignment: viewport
// rotation-alignment: map
} else if (u_rotate_with_map) {
// foreshortening factor to apply on pitched maps
// as a label goes from horizontal <=> vertical in angle
// it goes from 0% foreshortening to up to around 70% foreshortening
lowp float pitchfactor = 1.0 - cos(u_pitch * sin(u_pitch * 0.75));
lowp float lineangle = a_labelangle / 256.0 * 2.0 * PI;
highp float pitchfactor = 1.0 - cos(u_pitch * sin(u_pitch * 0.75));
// use the lineangle to position points a,b along the line
// project the points and calculate the label angle in projected space
// this calculation allows labels to be rendered unskewed on pitched maps
vec4 a = u_matrix * vec4(a_pos, 0, 1);
vec4 b = u_matrix * vec4(a_pos + vec2(cos(lineangle),sin(lineangle)), 0, 1);
lowp float angle = atan((b[1]/b[3] - a[1]/a[3])/u_aspect_ratio, b[0]/b[3] - a[0]/a[3]);
lowp float asin = sin(angle);
lowp float acos = cos(angle);
vec4 b = u_matrix * vec4(a_pos + vec2(cos(a_lineangle), sin(a_lineangle)), 0, 1);
highp float angle = atan((b[1] / b[3] - a[1] / a[3]) / u_aspect_ratio, b[0] / b[3] - a[0] / a[3]);
highp float asin = sin(angle);
highp float acos = cos(angle);
mat2 RotationMatrix = mat2(acos, -1.0 * asin, asin, acos);
highp float foreshortening = (1.0 - pitchfactor) + (pitchfactor * cos(angle * 2.0));
vec2 offset = RotationMatrix * (vec2(foreshortening, 1.0) * a_offset);
vec2 extrude = fontScale * u_extrude_scale * perspective_ratio * (offset / 64.0);
vec2 offset = RotationMatrix * (vec2((1.0-pitchfactor)+(pitchfactor*cos(angle*2.0)), 1.0) * a_offset);
vec2 extrude = fontScale * u_extrude_scale * (offset / 64.0);
gl_Position = u_matrix * vec4(a_pos, 0, 1) + vec4(extrude, 0, 0);
gl_Position.z += z * gl_Position.w;
gl_Position.z += clipUnusedGlyphAngles(v_size * perspective_ratio, layoutSize, a_minzoom, a_maxzoom) * gl_Position.w;
// pitch-alignment: viewport
// rotation-alignment: viewport
} else {
vec2 extrude = fontScale * u_extrude_scale * (a_offset / 64.0);
vec2 extrude = fontScale * u_extrude_scale * perspective_ratio * (a_offset / 64.0);
gl_Position = u_matrix * vec4(a_pos, 0, 1) + vec4(extrude, 0, 0);
}
float gamma_scale = gl_Position.w;
gl_Position.z +=
step(u_max_camera_distance * u_camera_to_center_distance, camera_to_anchor_distance) * gl_Position.w;
vec2 tex = a_tex / u_texsize;
vec2 fade_tex = vec2(a_labelminzoom / 255.0, 0.0);
v_gamma_scale = gl_Position.w / perspective_ratio;
v_data0 = vec4(tex.x, tex.y, fade_tex.x, fade_tex.y);
v_data1 = vec2(gamma_scale, size);
v_tex = a_tex / u_texsize;
// incidence_stretch is the ratio of how much y space a label takes up on a tile while drawn perpendicular to the viewport vs
// how much space it would take up if it were drawn flat on the tile
// Using law of sines, camera_to_anchor/sin(ground_angle) = camera_to_center/sin(incidence_angle)
// sin(incidence_angle) = 1/incidence_stretch
// Incidence angle 90 -> head on, sin(incidence_angle) = 1, no incidence stretch
// Incidence angle 1 -> very oblique, sin(incidence_angle) =~ 0, lots of incidence stretch
// ground_angle = u_pitch + PI/2 -> sin(ground_angle) = cos(u_pitch)
// This 2D calculation is only exactly correct when gl_Position.x is in the center of the viewport,
// but it's a close enough approximation for our purposes
highp float incidence_stretch = camera_to_anchor_distance / (u_camera_to_center_distance * cos(u_pitch));
// incidence_stretch only applies to the y-axis, but without re-calculating the collision tile, we can't
// adjust the size of only one axis. So, we do a crude approximation at placement time to get the aspect ratio
// about right, and then do the rest of the adjustment here: there will be some extra padding on the x-axis,
// but hopefully not too much.
// Never make the adjustment less than 1.0: instead of allowing collisions on the x-axis, be conservative on
// the y-axis.
highp float collision_adjustment = max(1.0, incidence_stretch / u_collision_y_stretch);
// Floor to 1/10th zoom to dodge precision issues that can cause partially hidden labels
highp float perspective_zoom_adjust = floor(log2(perspective_ratio * collision_adjustment) * 10.0);
v_fade_tex = vec2((a_labelminzoom + perspective_zoom_adjust) / 255.0, 0.0);
}
)MBGL_SHADER";
@@ -227,66 +273,73 @@ varying highp vec4 fill_color;
uniform highp vec4 u_fill_color;
#endif
#ifndef HAS_UNIFORM_u_halo_color
varying highp vec4 halo_color;
#else
uniform highp vec4 u_halo_color;
#endif
#ifndef HAS_UNIFORM_u_opacity
varying lowp float opacity;
#else
uniform lowp float u_opacity;
#endif
#ifndef HAS_UNIFORM_u_halo_width
varying lowp float halo_width;
#else
uniform lowp float u_halo_width;
#endif
#ifndef HAS_UNIFORM_u_halo_blur
varying lowp float halo_blur;
#else
uniform lowp float u_halo_blur;
#endif
uniform sampler2D u_texture;
uniform sampler2D u_fadetexture;
uniform highp float u_gamma_scale;
uniform bool u_is_text;
varying vec4 v_data0;
varying vec2 v_data1;
varying vec2 v_tex;
varying vec2 v_fade_tex;
varying float v_gamma_scale;
varying float v_size;
void main() {
#ifdef HAS_UNIFORM_u_fill_color
highp vec4 fill_color = u_fill_color;
#endif
#ifdef HAS_UNIFORM_u_halo_color
highp vec4 halo_color = u_halo_color;
#endif
#ifdef HAS_UNIFORM_u_opacity
lowp float opacity = u_opacity;
#endif
#ifdef HAS_UNIFORM_u_halo_width
lowp float halo_width = u_halo_width;
#endif
#ifdef HAS_UNIFORM_u_halo_blur
lowp float halo_blur = u_halo_blur;
#endif
vec2 tex = v_data0.xy;
vec2 fade_tex = v_data0.zw;
float gamma_scale = v_data1.x;
float size = v_data1.y;
float fontScale = u_is_text ? size / 24.0 : size;
float fontScale = u_is_text ? v_size / 24.0 : v_size;
lowp vec4 color = fill_color;
highp float gamma = EDGE_GAMMA / (fontScale * u_gamma_scale);
@@ -297,9 +350,9 @@ void main() {
buff = (6.0 - halo_width / fontScale) / SDF_PX;
}
lowp float dist = texture2D(u_texture, tex).a;
lowp float fade_alpha = texture2D(u_fadetexture, fade_tex).a;
highp float gamma_scaled = gamma * gamma_scale;
lowp float dist = texture2D(u_texture, v_tex).a;
lowp float fade_alpha = texture2D(u_fadetexture, v_fade_tex).a;
highp float gamma_scaled = gamma * v_gamma_scale;
highp float alpha = smoothstep(buff - gamma_scaled, buff + gamma_scaled, dist) * fade_alpha;
gl_FragColor = color * (alpha * opacity);