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-rw-r--r--progs/util/readtex.c353
1 files changed, 353 insertions, 0 deletions
diff --git a/progs/util/readtex.c b/progs/util/readtex.c
new file mode 100644
index 0000000000..7799416924
--- /dev/null
+++ b/progs/util/readtex.c
@@ -0,0 +1,353 @@
+/* readtex.c */
+
+/*
+ * Read an SGI .rgb image file and generate a mipmap texture set.
+ * Much of this code was borrowed from SGI's tk OpenGL toolkit.
+ */
+
+
+
+#include <GL/gl.h>
+#include <GL/glu.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+
+#ifndef SEEK_SET
+# define SEEK_SET 0
+#endif
+
+
+/*
+** RGB Image Structure
+*/
+
+typedef struct _TK_RGBImageRec {
+ GLint sizeX, sizeY;
+ GLint components;
+ unsigned char *data;
+} TK_RGBImageRec;
+
+
+
+/******************************************************************************/
+
+typedef struct _rawImageRec {
+ unsigned short imagic;
+ unsigned short type;
+ unsigned short dim;
+ unsigned short sizeX, sizeY, sizeZ;
+ unsigned long min, max;
+ unsigned long wasteBytes;
+ char name[80];
+ unsigned long colorMap;
+ FILE *file;
+ unsigned char *tmp, *tmpR, *tmpG, *tmpB, *tmpA;
+ unsigned long rleEnd;
+ GLuint *rowStart;
+ GLint *rowSize;
+} rawImageRec;
+
+/******************************************************************************/
+
+static void ConvertShort(unsigned short *array, long length)
+{
+ unsigned long b1, b2;
+ unsigned char *ptr;
+
+ ptr = (unsigned char *)array;
+ while (length--) {
+ b1 = *ptr++;
+ b2 = *ptr++;
+ *array++ = (unsigned short) ((b1 << 8) | (b2));
+ }
+}
+
+static void ConvertLong(GLuint *array, long length)
+{
+ unsigned long b1, b2, b3, b4;
+ unsigned char *ptr;
+
+ ptr = (unsigned char *)array;
+ while (length--) {
+ b1 = *ptr++;
+ b2 = *ptr++;
+ b3 = *ptr++;
+ b4 = *ptr++;
+ *array++ = (b1 << 24) | (b2 << 16) | (b3 << 8) | (b4);
+ }
+}
+
+static rawImageRec *RawImageOpen(const char *fileName)
+{
+ union {
+ int testWord;
+ char testByte[4];
+ } endianTest;
+ rawImageRec *raw;
+ GLenum swapFlag;
+ int x;
+
+ endianTest.testWord = 1;
+ if (endianTest.testByte[0] == 1) {
+ swapFlag = GL_TRUE;
+ } else {
+ swapFlag = GL_FALSE;
+ }
+
+ raw = (rawImageRec *)malloc(sizeof(rawImageRec));
+ if (raw == NULL) {
+ fprintf(stderr, "Out of memory!\n");
+ return NULL;
+ }
+ if ((raw->file = fopen(fileName, "rb")) == NULL) {
+ perror(fileName);
+ return NULL;
+ }
+
+ fread(raw, 1, 12, raw->file);
+
+ if (swapFlag) {
+ ConvertShort(&raw->imagic, 6);
+ }
+
+ raw->tmp = (unsigned char *)malloc(raw->sizeX*256);
+ raw->tmpR = (unsigned char *)malloc(raw->sizeX*256);
+ raw->tmpG = (unsigned char *)malloc(raw->sizeX*256);
+ raw->tmpB = (unsigned char *)malloc(raw->sizeX*256);
+ if (raw->sizeZ==4) {
+ raw->tmpA = (unsigned char *)malloc(raw->sizeX*256);
+ }
+ if (raw->tmp == NULL || raw->tmpR == NULL || raw->tmpG == NULL ||
+ raw->tmpB == NULL) {
+ fprintf(stderr, "Out of memory!\n");
+ return NULL;
+ }
+
+ if ((raw->type & 0xFF00) == 0x0100) {
+ x = raw->sizeY * raw->sizeZ * sizeof(GLuint);
+ raw->rowStart = (GLuint *)malloc(x);
+ raw->rowSize = (GLint *)malloc(x);
+ if (raw->rowStart == NULL || raw->rowSize == NULL) {
+ fprintf(stderr, "Out of memory!\n");
+ return NULL;
+ }
+ raw->rleEnd = 512 + (2 * x);
+ fseek(raw->file, 512, SEEK_SET);
+ fread(raw->rowStart, 1, x, raw->file);
+ fread(raw->rowSize, 1, x, raw->file);
+ if (swapFlag) {
+ ConvertLong(raw->rowStart, (long) (x/sizeof(GLuint)));
+ ConvertLong((GLuint *)raw->rowSize, (long) (x/sizeof(GLint)));
+ }
+ }
+ return raw;
+}
+
+static void RawImageClose(rawImageRec *raw)
+{
+
+ fclose(raw->file);
+ free(raw->tmp);
+ free(raw->tmpR);
+ free(raw->tmpG);
+ free(raw->tmpB);
+ if (raw->sizeZ>3) {
+ free(raw->tmpA);
+ }
+ free(raw);
+}
+
+static void RawImageGetRow(rawImageRec *raw, unsigned char *buf, int y, int z)
+{
+ unsigned char *iPtr, *oPtr, pixel;
+ int count, done = 0;
+
+ if ((raw->type & 0xFF00) == 0x0100) {
+ fseek(raw->file, (long) raw->rowStart[y+z*raw->sizeY], SEEK_SET);
+ fread(raw->tmp, 1, (unsigned int)raw->rowSize[y+z*raw->sizeY],
+ raw->file);
+
+ iPtr = raw->tmp;
+ oPtr = buf;
+ while (!done) {
+ pixel = *iPtr++;
+ count = (int)(pixel & 0x7F);
+ if (!count) {
+ done = 1;
+ return;
+ }
+ if (pixel & 0x80) {
+ while (count--) {
+ *oPtr++ = *iPtr++;
+ }
+ } else {
+ pixel = *iPtr++;
+ while (count--) {
+ *oPtr++ = pixel;
+ }
+ }
+ }
+ } else {
+ fseek(raw->file, 512+(y*raw->sizeX)+(z*raw->sizeX*raw->sizeY),
+ SEEK_SET);
+ fread(buf, 1, raw->sizeX, raw->file);
+ }
+}
+
+
+static void RawImageGetData(rawImageRec *raw, TK_RGBImageRec *final)
+{
+ unsigned char *ptr;
+ int i, j;
+
+ final->data = (unsigned char *)malloc((raw->sizeX+1)*(raw->sizeY+1)*4);
+ if (final->data == NULL) {
+ fprintf(stderr, "Out of memory!\n");
+ }
+
+ ptr = final->data;
+ for (i = 0; i < (int)(raw->sizeY); i++) {
+ RawImageGetRow(raw, raw->tmpR, i, 0);
+ RawImageGetRow(raw, raw->tmpG, i, 1);
+ RawImageGetRow(raw, raw->tmpB, i, 2);
+ if (raw->sizeZ>3) {
+ RawImageGetRow(raw, raw->tmpA, i, 3);
+ }
+ for (j = 0; j < (int)(raw->sizeX); j++) {
+ *ptr++ = *(raw->tmpR + j);
+ *ptr++ = *(raw->tmpG + j);
+ *ptr++ = *(raw->tmpB + j);
+ if (raw->sizeZ>3) {
+ *ptr++ = *(raw->tmpA + j);
+ }
+ }
+ }
+}
+
+
+static TK_RGBImageRec *tkRGBImageLoad(const char *fileName)
+{
+ rawImageRec *raw;
+ TK_RGBImageRec *final;
+
+ raw = RawImageOpen(fileName);
+ if (!raw) {
+ fprintf(stderr, "File not found\n");
+ return NULL;
+ }
+ final = (TK_RGBImageRec *)malloc(sizeof(TK_RGBImageRec));
+ if (final == NULL) {
+ fprintf(stderr, "Out of memory!\n");
+ return NULL;
+ }
+ final->sizeX = raw->sizeX;
+ final->sizeY = raw->sizeY;
+ final->components = raw->sizeZ;
+ RawImageGetData(raw, final);
+ RawImageClose(raw);
+ return final;
+}
+
+
+static void FreeImage( TK_RGBImageRec *image )
+{
+ free(image->data);
+ free(image);
+}
+
+
+/*
+ * Load an SGI .rgb file and generate a set of 2-D mipmaps from it.
+ * Input: imageFile - name of .rgb to read
+ * intFormat - internal texture format to use, or number of components
+ * Return: GL_TRUE if success, GL_FALSE if error.
+ */
+GLboolean LoadRGBMipmaps( const char *imageFile, GLint intFormat )
+{
+ GLint error;
+ GLenum format;
+ TK_RGBImageRec *image;
+
+ image = tkRGBImageLoad( imageFile );
+ if (!image) {
+ return GL_FALSE;
+ }
+
+ if (image->components==3) {
+ format = GL_RGB;
+ }
+ else if (image->components==4) {
+ format = GL_RGBA;
+ }
+ else {
+ /* not implemented */
+ fprintf(stderr,
+ "Error in LoadRGBMipmaps %d-component images not implemented\n",
+ image->components );
+ return GL_FALSE;
+ }
+
+ error = gluBuild2DMipmaps( GL_TEXTURE_2D,
+ intFormat,
+ image->sizeX, image->sizeY,
+ format,
+ GL_UNSIGNED_BYTE,
+ image->data );
+
+ FreeImage(image);
+ return error ? GL_FALSE : GL_TRUE;
+}
+
+
+
+/*
+ * Load an SGI .rgb file and return a pointer to the image data.
+ * Input: imageFile - name of .rgb to read
+ * Output: width - width of image
+ * height - height of image
+ * format - format of image (GL_RGB or GL_RGBA)
+ * Return: pointer to image data or NULL if error
+ */
+GLubyte *LoadRGBImage( const char *imageFile, GLint *width, GLint *height,
+ GLenum *format )
+{
+ TK_RGBImageRec *image;
+ GLint bytes;
+ GLubyte *buffer;
+
+ image = tkRGBImageLoad( imageFile );
+ if (!image) {
+ return NULL;
+ }
+
+ if (image->components==3) {
+ *format = GL_RGB;
+ }
+ else if (image->components==4) {
+ *format = GL_RGBA;
+ }
+ else {
+ /* not implemented */
+ fprintf(stderr,
+ "Error in LoadRGBImage %d-component images not implemented\n",
+ image->components );
+ return NULL;
+ }
+
+ *width = image->sizeX;
+ *height = image->sizeY;
+
+ bytes = image->sizeX * image->sizeY * image->components;
+ buffer = (GLubyte *) malloc(bytes);
+ if (!buffer)
+ return NULL;
+
+ memcpy( (void *) buffer, (void *) image->data, bytes );
+
+ FreeImage(image);
+
+ return buffer;
+}
+
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