Improve Pass:fill;

It can now fill an array texture to a multiview pass, copying to
the corresponding layers.

etc/shaders.h

@@ -1,11 +1,12 @@
 #include "shaders/unlit.vert.h"
 #include "shaders/unlit.frag.h"
 #include "shaders/font.frag.h"
-#include "shaders/fill.vert.h"
 #include "shaders/cubemap.vert.h"
 #include "shaders/cubemap.frag.h"
 #include "shaders/equirect.frag.h"
-#include "shaders/stereoblit.frag.h"
+#include "shaders/fill.vert.h"
+#include "shaders/fill_array.frag.h"
+#include "shaders/fill_stereo.frag.h"
 #include "shaders/animator.comp.h"
 #include "shaders/timewizard.comp.h"
 

etc/shaders/fill_array.frag

@@ -0,0 +1,11 @@
+#version 460
+#extension GL_EXT_multiview : require
+#extension GL_GOOGLE_include_directive : require
+
+#include "lovr.glsl"
+
+layout(set = 1, binding = 1) uniform texture2DArray ArrayTexture;
+
+vec4 lovrmain() {
+  return Color * getPixel(ArrayTexture, UV, ViewIndex);
+}

etc/shaders/lovr.glsl

@@ -157,7 +157,6 @@ layout(location = 14) in vec3 Tangent;
 vec4 getPixel(texture2D t, vec2 uv) { return texture(sampler2D(t, Sampler), uv); }
 vec4 getPixel(texture3D t, vec3 uvw) { return texture(sampler3D(t, Sampler), uvw); }
 vec4 getPixel(textureCube t, vec3 dir) { return texture(samplerCube(t, Sampler), dir); }
-vec4 getPixel(texture2DArray t, vec2 uv, uint layer) { return texture(sampler2DArray(t, Sampler), vec3(uv, layer)); }
 vec4 getPixel(texture2DArray t, vec2 uv, float layer) { return texture(sampler2DArray(t, Sampler), vec3(uv, layer)); }
 #endif
 

src/api/l_graphics.c

@@ -58,7 +58,6 @@ StringEntry lovrDefaultShader[] = {
   [SHADER_CUBEMAP] = ENTRY("cubemap"),
   [SHADER_EQUIRECT] = ENTRY("equirect"),
   [SHADER_FILL] = ENTRY("fill"),
-  [SHADER_STEREOBLIT] = ENTRY("stereoblit"),
   { 0 }
 };
 

src/modules/graphics/graphics.c

@@ -1618,9 +1618,13 @@ ShaderSource lovrGraphicsGetDefaultShaderSource(DefaultShader type, ShaderStage
       { lovr_shader_fill_vert, sizeof(lovr_shader_fill_vert) },
       { lovr_shader_unlit_frag, sizeof(lovr_shader_unlit_frag) }
     },
-    [SHADER_STEREOBLIT] = {
+    [SHADER_FILL_ARRAY] = {
       { lovr_shader_fill_vert, sizeof(lovr_shader_fill_vert) },
-      { lovr_shader_stereoblit_frag, sizeof(lovr_shader_stereoblit_frag) }
+      { lovr_shader_fill_array_frag, sizeof(lovr_shader_fill_array_frag) }
+    },
+    [SHADER_FILL_STEREO] = {
+      { lovr_shader_fill_vert, sizeof(lovr_shader_fill_vert) },
+      { lovr_shader_fill_stereo_frag, sizeof(lovr_shader_fill_stereo_frag) }
     }
   };
 
@@ -4989,10 +4993,20 @@ void lovrPassSkybox(Pass* pass, Texture* texture) {
 }
 
 void lovrPassFill(Pass* pass, Texture* texture) {
-  DefaultShader shader = SHADER_FILL;
-  if (texture && texture->info.layers == 2) {
-    shader = SHADER_STEREOBLIT;
+  DefaultShader shader;
+
+  if (!texture || texture->info.layers == 1) {
+    shader = SHADER_FILL;
+  } else if (pass->viewCount > 1 && texture->info.layers > 1) {
+    lovrCheck(texture->info.layers == pass->viewCount, "Texture layer counts must match to fill between them");
+    shader = SHADER_FILL_ARRAY;
+  } else if (pass->viewCount == 1 && texture->info.layers > 1) {
+    lovrCheck(texture->info.layers == 2, "To draw an array texture to a mono texture, it must have 2 layers");
+    shader = SHADER_FILL_STEREO;
+  } else {
+    lovrUnreachable();
   }
+
   lovrPassDraw(pass, &(Draw) {
     .mode = MESH_TRIANGLES,
     .shader = shader,

src/modules/graphics/graphics.h

@@ -273,7 +273,8 @@ typedef enum {
   SHADER_CUBEMAP,
   SHADER_EQUIRECT,
   SHADER_FILL,
-  SHADER_STEREOBLIT,
+  SHADER_FILL_ARRAY,
+  SHADER_FILL_STEREO,
   DEFAULT_SHADER_COUNT
 } DefaultShader;