1836 dont store texture in system memory unless absolutely necessary (#1843)

* #1836 Texture memory usage overhaul.  Much decrufting
- don't keep a copy of textures in system memory
- use GPU to downrez textures instead of reloading from cache
- use GPU to generate brightness/darkness bumpmaps

1 files changed, 35 insertions, 6 deletions

diff --git a/indra/newview/app_settings/shaders/class1/deferred/normgenF.glsl b/indra/newview/app_settings/shaders/class1/deferred/normgenF.glsl
index 902746366d..6d05d983f3 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/normgenF.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/normgenF.glsl
@@ -25,24 +25,53 @@
 
 /*[EXTRA_CODE_HERE]*/
 
+
+
+// generate a normal map using an approximation of the old emboss bump map "brightness/darkness" technique
+// srcMap is a source color image, output should be a normal
+
 out vec4 frag_color;
 
-uniform sampler2D alphaMap;
+uniform sampler2D srcMap;
 
 in vec2 vary_texcoord0;
 
 uniform float stepX;
 uniform float stepY;
 uniform float norm_scale;
+uniform int bump_code;
+
+#define BE_BRIGHTNESS 1
+#define BE_DARKNESS 2
+
+// get luminance or inverse luminance depending on bump_code
+float getBumpValue(vec2 texcoord)
+{
+    vec3 c = texture(srcMap, texcoord).rgb;
+
+    vec3 WEIGHT = vec3(0.2995, 0.5875, 0.1145);
+
+    float l = dot(c, WEIGHT);
+
+    if (bump_code == BE_DARKNESS)
+    {
+        l = 1.0 - l;
+    }
+
+    return l;
+}
+
 
 void main()
 {
-    float c = texture(alphaMap, vary_texcoord0).r;
+    float c = getBumpValue(vary_texcoord0).r;
+
+    float scaler = 512.0;
 
-    vec3 right = vec3(norm_scale, 0, (texture(alphaMap, vary_texcoord0+vec2(stepX, 0)).r-c)*255);
-    vec3 left = vec3(-norm_scale, 0, (texture(alphaMap, vary_texcoord0-vec2(stepX, 0)).r-c)*255);
-    vec3 up = vec3(0, -norm_scale, (texture(alphaMap, vary_texcoord0-vec2(0, stepY)).r-c)*255);
-    vec3 down = vec3(0, norm_scale, (texture(alphaMap, vary_texcoord0+vec2(0, stepY)).r-c)*255);
+    vec3 right = vec3(norm_scale, 0, (getBumpValue(vary_texcoord0+vec2(stepX, 0)).r-c)*scaler);
+    vec3 left = vec3(-norm_scale, 0, (getBumpValue(vary_texcoord0-vec2(stepX, 0)).r-c)*scaler);
+    vec3 up = vec3(0, -norm_scale, (getBumpValue(vary_texcoord0-vec2(0, stepY)).r-c)*scaler);
+    vec3 down = vec3(0, norm_scale, (getBumpValue(vary_texcoord0+vec2(0, stepY)).r-c)*scaler);
 
     vec3 norm = cross(right, down) + cross(down, left) + cross(left,up) + cross(up, right);