OpenGL transitions: squashed 5 commits into this one

vcl: Ignore i965’s shader compiler debug

(cherry picked from commit 928fe134ff6ea85f732b36a1ab11336f1d829531)

slideshow: Fix a few issues in the Glitter transition

Remove an unused variable, add comments, reduce the time a tile stays
black, and don’t rely on implicit casts of integers into floats.

(cherry picked from commit 22480b20130d10f4691cdf0a658040be7f36e47b)

slideshow: Improve the Ripple transition to match PowerPoint better

(cherry picked from commit 1d411cad5a7d78ead8cffb5da522f1e0fba31187)

slideshow: Improve the Vortex transition to match PowerPoint better

(cherry picked from commit d886fef25c5978dd4b07fa0e3ce2402874a6c29a)

slideshow: Define inverse() to bring back the GLSL version to 1.20

(cherry picked from commit a301da7cb6c562cd21983d9b3b34dc01235a82a5)

Change-Id: Ifd33ae982b762af3ea8d88b2b2de259aabeebc9a
Reviewed-on: https://gerrit.libreoffice.org/21116
Reviewed-by: Tor Lillqvist <tml@collabora.com>
Tested-by: Tor Lillqvist <tml@collabora.com>

1 files changed, 57 insertions, 8 deletions

diff --git a/slideshow/opengl/glitterVertexShader.glsl b/slideshow/opengl/glitterVertexShader.glsl
index 9fdaf2999a14..3704efdab90e 100644
--- a/slideshow/opengl/glitterVertexShader.glsl
+++ b/slideshow/opengl/glitterVertexShader.glsl
@@ -7,7 +7,7 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
  */
 
-#version 130
+#version 120
 
 #define M_PI 3.1415926535897932384626433832795
 
@@ -29,6 +29,49 @@ uniform ivec2 numTiles;
 uniform sampler2D permTexture;
 varying float angle;
 
+#if __VERSION__ < 140
+mat4 inverse(mat4 m)
+{
+    float a00 = m[0][0], a01 = m[0][1], a02 = m[0][2], a03 = m[0][3];
+    float a10 = m[1][0], a11 = m[1][1], a12 = m[1][2], a13 = m[1][3];
+    float a20 = m[2][0], a21 = m[2][1], a22 = m[2][2], a23 = m[2][3];
+    float a30 = m[3][0], a31 = m[3][1], a32 = m[3][2], a33 = m[3][3];
+
+    float b00 = a00 * a11 - a01 * a10;
+    float b01 = a00 * a12 - a02 * a10;
+    float b02 = a00 * a13 - a03 * a10;
+    float b03 = a01 * a12 - a02 * a11;
+    float b04 = a01 * a13 - a03 * a11;
+    float b05 = a02 * a13 - a03 * a12;
+    float b06 = a20 * a31 - a21 * a30;
+    float b07 = a20 * a32 - a22 * a30;
+    float b08 = a20 * a33 - a23 * a30;
+    float b09 = a21 * a32 - a22 * a31;
+    float b10 = a21 * a33 - a23 * a31;
+    float b11 = a22 * a33 - a23 * a32;
+
+    float det = b00 * b11 - b01 * b10 + b02 * b09 + b03 * b08 - b04 * b07 + b05 * b06;
+
+    return mat4(
+        a11 * b11 - a12 * b10 + a13 * b09,
+        a02 * b10 - a01 * b11 - a03 * b09,
+        a31 * b05 - a32 * b04 + a33 * b03,
+        a22 * b04 - a21 * b05 - a23 * b03,
+        a12 * b08 - a10 * b11 - a13 * b07,
+        a00 * b11 - a02 * b08 + a03 * b07,
+        a32 * b02 - a30 * b05 - a33 * b01,
+        a20 * b05 - a22 * b02 + a23 * b01,
+        a10 * b10 - a11 * b08 + a13 * b06,
+        a01 * b08 - a00 * b10 - a03 * b06,
+        a30 * b04 - a31 * b02 + a33 * b00,
+        a21 * b02 - a20 * b04 - a23 * b00,
+        a11 * b07 - a10 * b09 - a12 * b06,
+        a00 * b09 - a01 * b07 + a02 * b06,
+        a31 * b01 - a30 * b03 - a32 * b00,
+        a20 * b03 - a21 * b01 + a22 * b00) / det;
+}
+#endif
+
 float snoise(vec2 p)
 {
     return texture2D(permTexture, p).r;
@@ -57,22 +100,28 @@ mat4 rotationMatrix(vec3 axis, float angle)
 
 void main( void )
 {
-    // There are 18 vertices in an hexagon
-    int instanceID = gl_VertexID / 18;
+    vec2 pos = (center.xy + 1.0) / 2.0;
 
-    vec2 pos = (center.xy + 1) / 2;
+    // 0..1 pseudo-random value used to randomize the tile’s start time.
     float fuzz = snoise(pos);
+
     float startTime = pos.x * 0.5 + fuzz * 0.25;
     float endTime = startTime + 0.25;
-    float actualTime = clamp((time - startTime) / (endTime - startTime), 0, 1);
-    angle = actualTime * M_PI * 2;
+
+    // Scale the transition time to minimize the time a tile will stay black.
+    float transitionTime = clamp((time - startTime) / (endTime - startTime), 0.0, 1.0);
+    if (transitionTime < 0.5)
+        transitionTime = transitionTime * 0.3 / 0.5;
+    else
+        transitionTime = (transitionTime * 0.3 / 0.5) + 0.4;
+    angle = transitionTime * M_PI * 2.0;
 
     mat4 modelViewMatrix = u_modelViewMatrix * u_operationsTransformMatrix * u_sceneTransformMatrix * u_primitiveTransformMatrix;
-    mat4 transformMatrix = translationMatrix(center) * rotationMatrix(vec3(0, 1, 0), angle) * translationMatrix(-center);
+    mat4 transformMatrix = translationMatrix(center) * rotationMatrix(vec3(0.0, 1.0, 0.0), angle) * translationMatrix(-center);
 
     mat3 normalMatrix = mat3(transpose(inverse(transformMatrix)));
     gl_Position = u_projectionMatrix * modelViewMatrix * transformMatrix * vec4(a_position, 1.0);
-    v_texturePosition = vec2((a_position.x + 1) / 2, (1 - a_position.y) / 2);
+    v_texturePosition = vec2((a_position.x + 1.0) / 2.0, (1.0 - a_position.y) / 2.0);
     v_normal = normalize(normalMatrix * a_normal);
 }