--- /dev/null
+/*
+
+Copyright (c) 2002, Calum Robinson
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+* Redistributions of source code must retain the above copyright notice, this
+ list of conditions and the following disclaimer.
+
+* Redistributions in binary form must reproduce the above copyright notice,
+ this list of conditions and the following disclaimer in the documentation
+ and/or other materials provided with the distribution.
+
+* Neither the name of the author nor the names of its contributors may be used
+ to endorse or promote products derived from this software without specific
+ prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+*/
+
+/*
+ * Texture.c
+ * AppleFlurry
+ *
+ * Created by calumr on Sat Jul 07 2001.
+ * Copyright (c) 2001 __CompanyName__. All rights reserved.
+ *
+ */
+
+#include "flurry.h"
+
+#include <GL/gl.h>
+#include <GL/glu.h>
+
+#include <stdlib.h>
+#include <math.h>
+
+static GLubyte smallTextureArray[32][32];
+static GLubyte bigTextureArray[256][256][2];
+GLuint theTexture = 0;
+
+/* simple smoothing routine */
+static void SmoothTexture(void)
+{
+ GLubyte filter[32][32];
+ int i,j;
+ float t;
+ for (i=1;i<31;i++)
+ {
+ for (j=1;j<31;j++)
+ {
+ t = (float) smallTextureArray[i][j]*4;
+ t += (float) smallTextureArray[i-1][j];
+ t += (float) smallTextureArray[i+1][j];
+ t += (float) smallTextureArray[i][j-1];
+ t += (float) smallTextureArray[i][j+1];
+ t /= 8.0f;
+ filter[i][j] = (GLubyte) t;
+ }
+ }
+ for (i=1;i<31;i++)
+ {
+ for (j=1;j<31;j++)
+ {
+ smallTextureArray[i][j] = filter[i][j];
+ }
+ }
+}
+
+/* add some randomness to texture data */
+static void SpeckleTexture(void)
+{
+ int i,j;
+ int speck;
+ float t;
+ for (i=2;i<30;i++)
+ {
+ for (j=2;j<30;j++)
+ {
+ speck = 1;
+ while (speck <= 32 && random() % 2)
+ {
+ t = (float) MIN_(255,smallTextureArray[i][j]+speck);
+ smallTextureArray[i][j] = (GLubyte) t;
+ speck+=speck;
+ }
+ speck = 1;
+ while (speck <= 32 && random() % 2)
+ {
+ t = (float) MAX_(0,smallTextureArray[i][j]-speck);
+ smallTextureArray[i][j] = (GLubyte) t;
+ speck+=speck;
+ }
+ }
+ }
+}
+
+static void MakeSmallTexture(void)
+{
+ static int firstTime = 1;
+ int i,j;
+ float r,t;
+ if (firstTime)
+ {
+ firstTime = 0;
+ for (i=0;i<32;i++)
+ {
+ for (j=0;j<32;j++)
+ {
+ r = (float) sqrt((i-15.5)*(i-15.5)+(j-15.5)*(j-15.5));
+ if (r > 15.0f)
+ {
+ smallTextureArray[i][j] = 0;
+ }
+ else
+ {
+ t = 255.0f * (float) cos(r*M_PI/31.0);
+ smallTextureArray[i][j] = (GLubyte) t;
+ }
+ }
+ }
+ }
+ else
+ {
+ for (i=0;i<32;i++)
+ {
+ for (j=0;j<32;j++)
+ {
+ r = (float) sqrt((i-15.5)*(i-15.5)+(j-15.5)*(j-15.5));
+ if (r > 15.0f)
+ {
+ t = 0.0f;
+ }
+ else
+ {
+ t = 255.0f * (float) cos(r*M_PI/31.0);
+ }
+ smallTextureArray[i][j] = (GLubyte) MIN_(255,(t+smallTextureArray[i][j]+smallTextureArray[i][j])/3);
+ }
+ }
+ }
+ SpeckleTexture();
+ SmoothTexture();
+ SmoothTexture();
+}
+
+static void CopySmallTextureToBigTexture(int k, int l)
+{
+ int i,j;
+ for (i=0;i<32;i++)
+ {
+ for (j=0;j<32;j++)
+ {
+ bigTextureArray[i+k][j+l][0] = smallTextureArray[i][j];
+ bigTextureArray[i+k][j+l][1] = smallTextureArray[i][j];
+ }
+ }
+}
+
+static void AverageLastAndFirstTextures(void)
+{
+ int i,j;
+ int t;
+ for (i=0;i<32;i++)
+ {
+ for (j=0;j<32;j++)
+ {
+ t = (smallTextureArray[i][j] + bigTextureArray[i][j][0]) / 2;
+ smallTextureArray[i][j] = (GLubyte) MIN_(255,t);
+ }
+ }
+}
+
+void MakeTexture()
+{
+ int i,j;
+ for (i=0;i<8;i++)
+ {
+ for (j=0;j<8;j++)
+ {
+ if (i==7 && j==7)
+ {
+ AverageLastAndFirstTextures();
+ }
+ else
+ {
+ MakeSmallTexture();
+ }
+ CopySmallTextureToBigTexture(i*32,j*32);
+ }
+ }
+
+ glPixelStorei(GL_UNPACK_ALIGNMENT,1);
+
+ glGenTextures(1, &theTexture);
+ glBindTexture(GL_TEXTURE_2D, theTexture);
+
+ /* Set the tiling mode (this is generally always GL_REPEAT). */
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
+
+ /* Set the filtering. */
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_NEAREST);
+
+ gluBuild2DMipmaps(GL_TEXTURE_2D, 2, 256, 256, GL_LUMINANCE_ALPHA, GL_UNSIGNED_BYTE, bigTextureArray);
+ glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
+}
projects / xscreensaver / blobdiff