diff options
Diffstat (limited to 'game/src/Game/GameSession/TerrainMap.gdshader')
| -rw-r--r-- | game/src/Game/GameSession/TerrainMap.gdshader | 173 |
1 files changed, 108 insertions, 65 deletions
diff --git a/game/src/Game/GameSession/TerrainMap.gdshader b/game/src/Game/GameSession/TerrainMap.gdshader index 487401f..98f9efd 100644 --- a/game/src/Game/GameSession/TerrainMap.gdshader +++ b/game/src/Game/GameSession/TerrainMap.gdshader @@ -13,100 +13,140 @@ uniform sampler2D province_colour_tex: repeat_enable, filter_nearest; uniform uint hover_index; // Index of the currently selected province uniform uint selected_index; +// How much to mix between the near detailed map (0) and the far parchment map (1) +uniform float parchment_mix; // Cosmetic terrain textures uniform sampler2DArray terrain_tex: repeat_enable, filter_linear; -// The number of times the terrain textures should tile vertically +// Factor converting pixels to terrain tile size uniform float terrain_tile_factor; // Map stripe mask texture uniform sampler2D stripe_tex: repeat_enable, filter_linear; -// The number of times the stripe texture should tile vertically +// Factor converting pixels to stripe tile size uniform float stripe_tile_factor; +// Map parchment overlay texture +uniform sampler2D overlay_tex: repeat_enable, filter_linear; +// Factor converting pixels to overlay tile size +uniform float overlay_tile_factor; // Land map tint uniform sampler2D colormap_land_tex: repeat_enable, filter_linear; // Water map tint uniform sampler2D colormap_water_tex: repeat_enable, filter_linear; +// Overlay map tint +uniform sampler2D colormap_overlay_tex: repeat_enable, filter_linear; -const vec3 highlight_colour = vec3(1.0); -// Rec.709 luma coefficients -const vec3 luma_weights = vec3(0.2126, 0.7152, 0.0722); - -struct args_t { - vec2 uv, half_pixel_size; // Components for calculating province sampling UV - float stripe_mask; // Stripe mask value - between 0 (base) and 1 (stripe) +struct terrain_args_t { + vec2 uv, half_pixel_size; // Components for calculating terrain sampling UV vec2 terrain_uv; // UV coordinates scaled for terrain texture tiling - vec3 land_tint_colour, water_tint_colour; // Colours for tinting terrain + vec3 land_tint_colour, water_tint_colour; // Colours for tinting the terrain }; -// TODO - add parchment overlay, borders, coastlines, rivers, fog of war -// (when borders are added we can move province colour calculations out of get_terrain_colour -// and into get_map_colour, as we won't need to blend along the borders between provinces) - -// This calculates the terrain and base-stripe province colours, blends them together, and then returns -// either the blended colour or just the terrain colour depending on whether the province colour's alpha -// value was set. It also highlights the result if the province is currently selected and/or hovered over. -vec3 get_terrain_colour(const args_t args, const vec2 corner) { - // Find the province and terrain indices at the specified corner of a pixel centred on uv - uvec3 province_data = read_uvec3(fma(corner, args.half_pixel_size, args.uv)); - uint province_index = uvec2_to_uint(province_data.rg); - uint terrain_index = province_data.b; - - // Get the tinted terrain colour at the current position - vec3 terrain_colour = texture(terrain_tex, vec3(args.terrain_uv, float(terrain_index))).rgb; - vec3 tint_colour = mix(args.land_tint_colour, args.water_tint_colour, float(terrain_index == 0u)); - vec3 tinted_terrain_colour = mix(terrain_colour, tint_colour, 0.3); - float terrain_luma = dot(tinted_terrain_colour, luma_weights); +// Calculate terrain colour at the specified corner of the current pixel +vec3 get_terrain_colour(const terrain_args_t terrain_args, const vec2 corner) { + // Find the terrain index at the specified corner of the current pixel + uint terrain_index = read_uvec3(fma(corner, terrain_args.half_pixel_size, terrain_args.uv)).z; - // Get base and stripe colours for province at the current position - province_data.r *= 2u; // Double "x coordinate" as colours come in (base, stripe) pairs - vec4 province_base_colour = texelFetch(province_colour_tex, ivec2(province_data.rg), 0); - province_data.r += 1u; // Add 1 to "x coordinate" to move from base to strip colour - vec4 province_stripe_colour = texelFetch(province_colour_tex, ivec2(province_data.rg), 0); - // Blend the base and stripe colours according to the current position's stripe mask value - vec4 province_colour = mix(province_base_colour, province_stripe_colour, args.stripe_mask); + // Get the tinted land colour at the current position + vec3 land_colour = texture(terrain_tex, vec3(terrain_args.terrain_uv, float(terrain_index))).rgb; + land_colour = mix(land_colour, terrain_args.land_tint_colour, 0.3); - // Darken the province colour, use it to tint the monochrome terrain colour, and re-lighten the result - province_colour.rgb = mix(vec3(terrain_luma), province_colour.rgb - 0.7, 0.3) * 1.5; + // TODO - proper water texture + vec3 water_colour = terrain_args.water_tint_colour; - // Show the terrain colour if the province colour has no alpha, otherwise show the province colour - vec3 mixed_colour = mix(tinted_terrain_colour, province_colour.rgb, float(province_colour.a != 0.0)); + // Select land or water colour based on the terrain index (0 is water, otherwise land) + vec3 terrain_colour = mix(land_colour, water_colour, float(terrain_index == 0u)); - float highlight_mix_val = 0.4 * (float(province_index == hover_index) + float(province_index == selected_index)) * float(province_index != 0u); - return mix(mixed_colour, highlight_colour, highlight_mix_val); + return terrain_colour; } -// Rescale UV coordinates to remove squashing caused by normalisation -vec2 denormalise(const vec2 uv, const vec2 dims) { - return vec2(uv.x * dims.x / dims.y, uv.y); +// Blend together terrain colours from the four corners of the current pixel +vec3 mix_terrain_colour(const terrain_args_t terrain_args, const vec2 pixel_offset) { + return mix( + mix(get_terrain_colour(terrain_args, vec2(-1, -1)), get_terrain_colour(terrain_args, vec2(+1, -1)), pixel_offset.x), + mix(get_terrain_colour(terrain_args, vec2(-1, +1)), get_terrain_colour(terrain_args, vec2(+1, +1)), pixel_offset.x), + pixel_offset.y + ); } -// Calculate position-specific values and then calculate and blend map colours at the four corners -// of a pixel centred at uv in order to have smooth transitions between terrain types. -vec3 get_map_colour(vec2 uv) { - args_t args; - args.uv = uv; +// Mix overlay and base colours, used for the parchment map +vec3 mix_overlay(const vec3 overlay_colour, const vec3 base_colour) { + return mix( + 2.0 * overlay_colour * base_colour, + 1.0 - 2.0 * (1.0 - overlay_colour) * (1.0 - base_colour), + greaterThanEqual(overlay_colour.rrb, vec3(0.5)) + ); +} +// Calculate map colour at specified UV coordinates, combining terrain, province base and stripe colour, +// parchment overlay, and highlighting the result if it is a hovered over and/or selected province. +vec3 get_map_colour(vec2 uv) { vec2 map_size = vec2(textureSize(province_shape_tex, 0).xy) * province_shape_subdivisions; - vec2 uv_centred = fma(uv, map_size, vec2(0.5)); - vec2 pixel_offset = fract(uv_centred); - args.half_pixel_size = 0.49 / map_size; + vec2 uv_map_pixels = fma(uv, map_size, vec2(0.5)); + // Offset of uv_map_pixels from the top left corner of the current pixel + vec2 pixel_offset = fract(uv_map_pixels); + + terrain_args_t terrain_args; + terrain_args.uv = uv; + terrain_args.half_pixel_size = 0.49 / map_size; + // Terrain texture tiling UV + terrain_args.terrain_uv = 0.5 - uv_map_pixels * terrain_tile_factor; - // UV coords adjusted to remove squashing caused by normalisation relative to map dimensions - vec2 unscaled_uv = denormalise(uv, map_size); + vec2 colormap_uv = vec2(uv.x, 1.0 - uv.y); + // Terrain tinting colours + terrain_args.land_tint_colour = texture(colormap_land_tex, colormap_uv).rgb; + terrain_args.water_tint_colour = texture(colormap_water_tex, colormap_uv).rgb; + // Parchment tint colour + vec3 overlay_tint_colour = texture(colormap_overlay_tex, colormap_uv).rgb; + + // Blended terrain colour (average of four corners of current pixel) + vec3 terrain_colour = mix_terrain_colour(terrain_args, pixel_offset); - vec2 stripe_uv = unscaled_uv * stripe_tile_factor; + vec2 stripe_uv = uv_map_pixels * stripe_tile_factor; // Stripe mask value - between 0 (base) and 1 (stripe) - args.stripe_mask = texture(stripe_tex, stripe_uv).b; + float stripe_mask = texture(stripe_tex, stripe_uv).b; - args.terrain_uv = 0.5 - unscaled_uv * terrain_tile_factor; - vec2 colormap_uv = vec2(uv.x, 1.0 - uv.y); - args.land_tint_colour = texture(colormap_land_tex, colormap_uv).rgb; - args.water_tint_colour = texture(colormap_water_tex, colormap_uv).rgb; + vec2 overlay_uv = vec2(uv_map_pixels.x, map_size.y - uv_map_pixels.y) * overlay_tile_factor; + // Parchment overlay colour + vec3 overlay_colour = texture(overlay_tex, overlay_uv).rgb; - return mix( - mix(get_terrain_colour(args, vec2(-1, -1)), get_terrain_colour(args, vec2(+1, -1)), pixel_offset.x), - mix(get_terrain_colour(args, vec2(-1, +1)), get_terrain_colour(args, vec2(+1, +1)), pixel_offset.x), - pixel_offset.y - ); + // Current province index as a pair of byte coordinates and as a combined 16 bit value + uvec2 province_data = read_uvec3(uv).xy; + uint province_index = uvec2_to_uint(province_data); + + // Get base and stripe colours for province at the current position + province_data.x *= 2u; // Double "x coordinate" as colours come in (base, stripe) pairs + vec4 province_base_colour = texelFetch(province_colour_tex, ivec2(province_data), 0); + province_data.x += 1u; // Add 1 to "x coordinate" to move from base to strip colour + vec4 province_stripe_colour = texelFetch(province_colour_tex, ivec2(province_data), 0); + // Blend the base and stripe colours according to the current position's stripe mask value + vec4 province_colour = mix(province_base_colour, province_stripe_colour, stripe_mask); + // Darken the province colour + province_colour.rgb -= 0.7; + + // Rec.709 luma coefficients + const vec3 luma_weights = vec3(0.2126, 0.7152, 0.0722); + float terrain_luma = dot(terrain_colour, luma_weights); + + // Near colour is either the terrain's luma component tinted with the province colour and brightened, + // or the normal terrain colour + vec3 near_province_colour = mix(vec3(terrain_luma), province_colour.rgb, 0.3) * 1.5; + vec3 near_colour = mix(near_province_colour, terrain_colour, float(province_colour.a == 0.0)); + + // Far colour is either the province colour mixed with the overlay texture, tinted with the overlay colormap and brightened, + // or the normal terrain colour mixed with the overlay texture (primarily for water) + vec3 far_province_colour = mix_overlay(overlay_colour, province_colour.rgb); + far_province_colour = mix(overlay_tint_colour, far_province_colour, 0.3) * 1.5; + vec3 far_terrain_colour = mix_overlay(overlay_colour, terrain_colour); + vec3 far_colour = mix(far_province_colour, far_terrain_colour, float(province_colour.a == 0.0)); + + // Blend the near (detailed terrain) and far (parchment) colours according to the parchment mix factor (0 for near, 1 for far) + vec3 final_colour = mix(near_colour, far_colour, parchment_mix); + + // Significantly brighted the colour if it is hovered over and/or selected, but not if it has province index 0 (all invalid pixels) + const vec3 highlight_colour = vec3(1.0); + float highlight_mix_val = 0.4 * (float(province_index == hover_index) + float(province_index == selected_index)) * float(province_index != 0u); + vec3 highlighted_colour = mix(final_colour, highlight_colour, highlight_mix_val); + + return highlighted_colour; } // Convert from standard RGB to linear colour space (Godot requires the output to be linear) @@ -119,5 +159,8 @@ vec3 srgb_to_linear(vec3 srgb) { } void fragment() { + + // TODO - add borders, coastlines, rivers, fog of war + ALBEDO = srgb_to_linear(get_map_colour(UV)); } |