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-rw-r--r--progs/glsl/Makefile278
-rw-r--r--progs/glsl/texaaline.c369
2 files changed, 499 insertions, 148 deletions
diff --git a/progs/glsl/Makefile b/progs/glsl/Makefile
index 8e61ab690b..71db895d1d 100644
--- a/progs/glsl/Makefile
+++ b/progs/glsl/Makefile
@@ -5,48 +5,69 @@ include $(TOP)/configs/current
INCDIR = $(TOP)/include
-LIB_DEP = $(TOP)/$(LIB_DIR)/$(GL_LIB_NAME) $(TOP)/$(LIB_DIR)/$(GLU_LIB_NAME) $(TOP)/$(LIB_DIR)/$(GLUT_LIB_NAME)
+LIB_DEP = \
+ $(TOP)/$(LIB_DIR)/$(GL_LIB_NAME) \
+ $(TOP)/$(LIB_DIR)/$(GLU_LIB_NAME) \
+ $(TOP)/$(LIB_DIR)/$(GLUT_LIB_NAME)
LIBS = -L$(TOP)/$(LIB_DIR) -l$(GLUT_LIB) -l$(GLU_LIB) -l$(GL_LIB) $(APP_LIB_DEPS)
-PROGS = \
- array \
- bitmap \
- brick \
- bump \
- convolutions \
- deriv \
- identity \
- fragcoord \
- linktest \
- mandelbrot \
- multinoise \
- multitex \
- noise \
- noise2 \
- points \
- pointcoord \
- samplers \
- samplers_array \
- shadow_sampler \
- skinning \
- texdemo1 \
- toyball \
- twoside \
- trirast \
- vert-or-frag-only \
- vert-tex
+INCLUDE_DIRS = -I$(TOP)/progs/util
+
+DEMO_SOURCES = \
+ array.c \
+ bitmap.c \
+ brick.c \
+ bump.c \
+ convolutions.c \
+ deriv.c \
+ fragcoord.c \
+ identity.c \
+ linktest.c \
+ mandelbrot.c \
+ multinoise.c \
+ multitex.c \
+ noise.c \
+ noise2.c \
+ pointcoord.c \
+ points.c \
+ samplers.c \
+ shadow_sampler.c \
+ skinning.c \
+ texaaline.c \
+ texdemo1.c \
+ toyball.c \
+ trirast.c \
+ twoside.c \
+ vert-or-frag-only.c \
+ vert-tex.c
+
+UTIL_HEADERS = \
+ extfuncs.h \
+ shaderutil.h \
+ readtex.h
+
+UTIL_SOURCES = \
+ shaderutil.c \
+ readtex.c
+
+UTIL_OBJS = $(UTIL_SOURCES:.c=.o)
+
+
+PROGS = $(DEMO_SOURCES:%.c=%)
+
##### RULES #####
-.SUFFIXES:
-.SUFFIXES: .c
+# make .o file from .c file:
+.c.o:
+ $(APP_CC) -c -I$(INCDIR) $(CFLAGS) $< -o $@
-# make executable from .c file:
-.c: $(LIB_DEP)
- $(APP_CC) -I$(INCDIR) $(CFLAGS) $(LDFLAGS) $< $(LIBS) -o $@
+# make executable from .o files
+.o:
+ $(APP_CC) $(INCLUDES) $(CFLAGS) $(LDFLAGS) $< $(UTIL_OBJS) $(LIBS) -o $@
##### TARGETS #####
@@ -54,202 +75,163 @@ PROGS = \
default: $(PROGS)
+clean:
+ -rm -f $(PROGS)
+ -rm -f *.o *~
+ -rm -f extfuncs.h
+ -rm -f shaderutil.*
+
+
##### Extra dependencies
-extfuncs.h: $(TOP)/progs/util/extfuncs.h
- cp $< .
+extfuncs.h:
+ cp $(TOP)/progs/util/extfuncs.h .
+readtex.c:
+ cp $(TOP)/progs/util/readtex.c .
-readtex.c: $(TOP)/progs/util/readtex.c
- cp $< .
+readtex.h:
+ cp $(TOP)/progs/util/readtex.h .
-readtex.h: $(TOP)/progs/util/readtex.h
- cp $< .
+shaderutil.c:
+ cp $(TOP)/progs/util/shaderutil.c .
-readtex.o: readtex.c readtex.h
- $(APP_CC) -c -I$(INCDIR) $(CFLAGS) readtex.c
+shaderutil.h:
+ cp $(TOP)/progs/util/shaderutil.h .
-shaderutil.c: $(TOP)/progs/util/shaderutil.c
- cp $< .
-shaderutil.h: $(TOP)/progs/util/shaderutil.h
- cp $< .
+array.o: $(UTIL_HEADERS)
-shaderutil.o: shaderutil.c shaderutil.h
- $(APP_CC) -c -I$(INCDIR) $(CFLAGS) shaderutil.c
+array: array.o $(UTIL_OBJS)
+bitmap.o: $(UTIL_HEADERS)
-array.o: array.c extfuncs.h shaderutil.h
- $(APP_CC) -c -I$(INCDIR) $(CFLAGS) array.c
+bitmap: bitmap.o $(UTIL_OBJS)
-array: array.o shaderutil.o
- $(APP_CC) -I$(INCDIR) $(CFLAGS) $(LDFLAGS) array.o shaderutil.o $(LIBS) -o $@
+brick.o: $(UTIL_HEADERS)
-bitmap.o: bitmap.c extfuncs.h shaderutil.h
- $(APP_CC) -c -I$(INCDIR) $(CFLAGS) bitmap.c
+brick: brick.o $(UTIL_OBJS)
-bitmap: bitmap.o shaderutil.o
- $(APP_CC) -I$(INCDIR) $(CFLAGS) $(LDFLAGS) bitmap.o shaderutil.o $(LIBS) -o $@
+bump.o: $(UTIL_HEADERS)
-brick.o: brick.c extfuncs.h shaderutil.h
- $(APP_CC) -c -I$(INCDIR) $(CFLAGS) brick.c
+bump: bump.o $(UTIL_OBJS)
-brick: brick.o shaderutil.o
- $(APP_CC) -I$(INCDIR) $(CFLAGS) $(LDFLAGS) brick.o shaderutil.o $(LIBS) -o $@
+convolutions.o: $(UTIL_HEADERS)
-bump.o: bump.c extfuncs.h shaderutil.h
- $(APP_CC) -c -I$(INCDIR) $(CFLAGS) bump.c
+convolutions: convolutions.o $(UTIL_OBJS)
-bump: bump.o shaderutil.o
- $(APP_CC) -I$(INCDIR) $(CFLAGS) $(LDFLAGS) bump.o shaderutil.o $(LIBS) -o $@
+deriv.o: deriv.c $(UTIL_HEADERS)
-convolutions.o: convolutions.c readtex.h
- $(APP_CC) -c -I$(INCDIR) $(CFLAGS) convolutions.c
+deriv: deriv.o $(UTIL_OBJS)
-convolutions: convolutions.o readtex.o
- $(APP_CC) -I$(INCDIR) $(CFLAGS) $(LDFLAGS) convolutions.o readtex.o $(LIBS) -o $@
+identity.o: $(UTIL_HEADERS)
-deriv.o: deriv.c extfuncs.h shaderutil.h
- $(APP_CC) -c -I$(INCDIR) $(CFLAGS) deriv.c
+identity: identity.o $(UTIL_OBJS)
-deriv: deriv.o shaderutil.o
- $(APP_CC) -I$(INCDIR) $(CFLAGS) $(LDFLAGS) deriv.o shaderutil.o $(LIBS) -o $@
+fragcoord.o: $(UTIL_HEADERS)
-identity.o: identity.c extfuncs.h shaderutil.h
- $(APP_CC) -c -I$(INCDIR) $(CFLAGS) identity.c
+fragcoord: fragcoord.o $(UTIL_OBJS)
-identity: identity.o shaderutil.o
- $(APP_CC) -I$(INCDIR) $(CFLAGS) $(LDFLAGS) identity.o shaderutil.o $(LIBS) -o $@
+linktest.o: $(UTIL_HEADERS)
-fragcoord.o: fragcoord.c extfuncs.h shaderutil.h
- $(APP_CC) -c -I$(INCDIR) $(CFLAGS) fragcoord.c
+linktest: linktest.o $(UTIL_OBJS)
-fragcoord: fragcoord.o shaderutil.o
- $(APP_CC) -I$(INCDIR) $(CFLAGS) $(LDFLAGS) fragcoord.o shaderutil.o $(LIBS) -o $@
+mandelbrot.o: $(UTIL_HEADERS)
-linktest.o: linktest.c extfuncs.h shaderutil.h
- $(APP_CC) -c -I$(INCDIR) $(CFLAGS) linktest.c
+mandelbrot: mandelbrot.o $(UTIL_OBJS)
-linktest: linktest.o shaderutil.o
- $(APP_CC) -I$(INCDIR) $(CFLAGS) $(LDFLAGS) linktest.o shaderutil.o $(LIBS) -o $@
-mandelbrot.o: mandelbrot.c extfuncs.h shaderutil.h
- $(APP_CC) -c -I$(INCDIR) $(CFLAGS) mandelbrot.c
+multinoise.o: $(UTIL_HEADERS)
-mandelbrot: mandelbrot.o shaderutil.o
- $(APP_CC) -I$(INCDIR) $(CFLAGS) $(LDFLAGS) mandelbrot.o shaderutil.o $(LIBS) -o $@
+multinoise: multinoise.o $(UTIL_OBJS)
-multitex.o: multitex.c extfuncs.h readtex.h shaderutil.h
- $(APP_CC) -c -I$(INCDIR) $(CFLAGS) multitex.c
-multitex: multitex.o readtex.o shaderutil.o
- $(APP_CC) -I$(INCDIR) $(CFLAGS) $(LDFLAGS) multitex.o readtex.o shaderutil.o $(LIBS) -o $@
+multitex.o: $(UTIL_HEADERS)
+multitex: multitex.o $(UTIL_OBJS)
-noise.o: noise.c extfuncs.h shaderutil.h
- $(APP_CC) -c -I$(INCDIR) $(CFLAGS) noise.c
-noise: noise.o shaderutil.o
- $(APP_CC) -I$(INCDIR) $(CFLAGS) $(LDFLAGS) noise.o shaderutil.o $(LIBS) -o $@
+noise.o: $(UTIL_HEADERS)
+noise: noise.o $(UTIL_OBJS)
-noise2.o: noise2.c extfuncs.h shaderutil.h
- $(APP_CC) -c -I$(INCDIR) $(CFLAGS) noise2.c
-noise2: noise2.o shaderutil.o
- $(APP_CC) -I$(INCDIR) $(CFLAGS) $(LDFLAGS) noise2.o shaderutil.o $(LIBS) -o $@
+noise2.o: $(UTIL_HEADERS)
+noise2: noise2.o $(UTIL_OBJS)
-points.o: points.c extfuncs.h shaderutil.h
- $(APP_CC) -c -I$(INCDIR) $(CFLAGS) points.c
-points: points.o shaderutil.o
- $(APP_CC) -I$(INCDIR) $(CFLAGS) $(LDFLAGS) points.o shaderutil.o $(LIBS) -o $@
+points.o: $(UTIL_HEADERS)
+points: points.o $(UTIL_OBJS)
-pointcoord.o: pointcoord.c readtex.h extfuncs.h shaderutil.h
- $(APP_CC) -c -I$(INCDIR) $(CFLAGS) pointcoord.c
-pointcoord: pointcoord.o readtex.o shaderutil.o
- $(APP_CC) -I$(INCDIR) $(CFLAGS) $(LDFLAGS) pointcoord.o readtex.o shaderutil.o $(LIBS) -o $@
+pointcoord.o: $(UTIL_HEADERS)
+pointcoord: pointcoord.o $(UTIL_OBJS)
-samplers.o: samplers.c readtex.h extfuncs.h shaderutil.h
- $(APP_CC) -c -I$(INCDIR) $(CFLAGS) samplers.c
-samplers: samplers.o readtex.o shaderutil.o
- $(APP_CC) -I$(INCDIR) $(CFLAGS) $(LDFLAGS) samplers.o readtex.o shaderutil.o $(LIBS) -o $@
+samplers.o: $(UTIL_HEADERS)
-samplers_array.o: samplers.c readtex.h extfuncs.h shaderutil.h
- $(APP_CC) -c -DSAMPLERS_ARRAY -I$(INCDIR) $(CFLAGS) samplers.c -o samplers_array.o
+samplers: samplers.o $(UTIL_OBJS)
-samplers_array: samplers_array.o readtex.o shaderutil.o
- $(APP_CC) -I$(INCDIR) $(CFLAGS) $(LDFLAGS) samplers_array.o readtex.o shaderutil.o $(LIBS) -o $@
-skinning.o: skinning.c readtex.h extfuncs.h shaderutil.h
- $(APP_CC) -c -I$(INCDIR) $(CFLAGS) skinning.c
+samplers_array.o: $(UTIL_HEADERS)
-skinning: skinning.o readtex.o shaderutil.o
- $(APP_CC) -I$(INCDIR) $(CFLAGS) $(LDFLAGS) skinning.o readtex.o shaderutil.o $(LIBS) -o $@
+samplers_array: samplers_array.o $(UTIL_OBJS)
-texdemo1.o: texdemo1.c readtex.h extfuncs.h shaderutil.h
- $(APP_CC) -c -I$(INCDIR) $(CFLAGS) texdemo1.c
+shadow_sampler.o: $(UTIL_HEADERS)
-texdemo1: texdemo1.o readtex.o shaderutil.o
- $(APP_CC) -I$(INCDIR) $(CFLAGS) $(LDFLAGS) texdemo1.o readtex.o shaderutil.o $(LIBS) -o $@
+shadow_sampler: shadow_sampler.o $(UTIL_OBJS)
-toyball.o: toyball.c extfuncs.h shaderutil.h
- $(APP_CC) -c -I$(INCDIR) $(CFLAGS) toyball.c
+skinning.o: $(UTIL_HEADERS)
-toyball: toyball.o shaderutil.o
- $(APP_CC) -I$(INCDIR) $(CFLAGS) $(LDFLAGS) toyball.o shaderutil.o $(LIBS) -o $@
+skinning: skinning.o $(UTIL_OBJS)
-twoside.o: twoside.c extfuncs.h shaderutil.h
- $(APP_CC) -c -I$(INCDIR) $(CFLAGS) twoside.c
+texaaline.o: $(UTIL_HEADERS)
-twoside: twoside.o shaderutil.o
- $(APP_CC) -I$(INCDIR) $(CFLAGS) $(LDFLAGS) twoside.o shaderutil.o $(LIBS) -o $@
+texaaline: texaaline.o $(UTIL_OBJS)
-trirast.o: trirast.c extfuncs.h shaderutil.h
- $(APP_CC) -c -I$(INCDIR) $(CFLAGS) trirast.c
+texdemo1.o: $(UTIL_HEADERS)
-trirast: trirast.o shaderutil.o
- $(APP_CC) -I$(INCDIR) $(CFLAGS) $(LDFLAGS) trirast.o shaderutil.o $(LIBS) -o $@
+texdemo1: texdemo1.o $(UTIL_OBJS)
-vert-or-frag-only.o: vert-or-frag-only.c extfuncs.h shaderutil.h
- $(APP_CC) -c -I$(INCDIR) $(CFLAGS) vert-or-frag-only.c
+toyball.o: $(UTIL_HEADERS)
-vert-or-frag-only: vert-or-frag-only.o shaderutil.o
- $(APP_CC) -I$(INCDIR) $(CFLAGS) $(LDFLAGS) vert-or-frag-only.o shaderutil.o $(LIBS) -o $@
+toyball: toyball.o $(UTIL_OBJS)
-vert-tex.o: vert-tex.c extfuncs.h shaderutil.h
- $(APP_CC) -c -I$(INCDIR) $(CFLAGS) vert-tex.c
+twoside.o: $(UTIL_HEADERS)
-vert-tex: vert-tex.o shaderutil.o
- $(APP_CC) -I$(INCDIR) $(CFLAGS) $(LDFLAGS) vert-tex.o shaderutil.o $(LIBS) -o $@
+twoside: twoside.o $(UTIL_OBJS)
+trirast.o: $(UTIL_HEADERS)
+trirast: trirast.o $(UTIL_OBJS)
-clean:
- -rm -f $(PROGS)
- -rm -f *.o *~
- -rm -f extfuncs.h
- -rm -f shaderutil.*
+
+vert-or-frag-only.o: $(UTIL_HEADERS)
+
+vert-or-frag-only: vert-or-frag-only.o $(UTIL_OBJS)
+
+
+vert-tex.o: $(UTIL_HEADERS)
+
+vert-tex: vert-tex.o $(UTIL_OBJS)
diff --git a/progs/glsl/texaaline.c b/progs/glsl/texaaline.c
new file mode 100644
index 0000000000..0b3cc84958
--- /dev/null
+++ b/progs/glsl/texaaline.c
@@ -0,0 +1,369 @@
+/**
+ * AA lines with texture mapped quads
+ *
+ * Brian Paul
+ * 9 Feb 2008
+ */
+
+
+#include <assert.h>
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#include <GL/gl.h>
+#include <GL/glut.h>
+#include <GL/glext.h>
+#include "extfuncs.h"
+
+
+static GLint WinWidth = 300, WinHeight = 300;
+static GLint win = 0;
+static GLfloat Width = 8.;
+
+/*
+ * Quad strip for line from v0 to v1:
+ *
+ 1 3 5 7
+ +---+---------------------+---+
+ | |
+ | *v0 v1* |
+ | |
+ +---+---------------------+---+
+ 0 2 4 6
+ */
+static void
+QuadLine(const GLfloat *v0, const GLfloat *v1, GLfloat width)
+{
+ GLfloat dx = v1[0] - v0[0];
+ GLfloat dy = v1[1] - v0[1];
+ GLfloat len = sqrt(dx*dx + dy*dy);
+ float dx0, dx1, dx2, dx3, dx4, dx5, dx6, dx7;
+ float dy0, dy1, dy2, dy3, dy4, dy5, dy6, dy7;
+
+ dx /= len;
+ dy /= len;
+
+ width *= 0.5; /* half width */
+ dx = dx * (width + 0.0);
+ dy = dy * (width + 0.0);
+
+ dx0 = -dx+dy; dy0 = -dy-dx;
+ dx1 = -dx-dy; dy1 = -dy+dx;
+
+ dx2 = 0+dy; dy2 = -dx+0;
+ dx3 = 0-dy; dy3 = +dx+0;
+
+ dx4 = 0+dy; dy4 = -dx+0;
+ dx5 = 0-dy; dy5 = +dx+0;
+
+ dx6 = dx+dy; dy6 = dy-dx;
+ dx7 = dx-dy; dy7 = dy+dx;
+
+ /*
+ printf("dx, dy = %g, %g\n", dx, dy);
+ printf(" dx0, dy0: %g, %g\n", dx0, dy0);
+ printf(" dx1, dy1: %g, %g\n", dx1, dy1);
+ printf(" dx2, dy2: %g, %g\n", dx2, dy2);
+ printf(" dx3, dy3: %g, %g\n", dx3, dy3);
+ */
+
+ glBegin(GL_QUAD_STRIP);
+ glTexCoord2f(0, 0);
+ glVertex2f(v0[0] + dx0, v0[1] + dy0);
+ glTexCoord2f(0, 1);
+ glVertex2f(v0[0] + dx1, v0[1] + dy1);
+
+ glTexCoord2f(0.5, 0);
+ glVertex2f(v0[0] + dx2, v0[1] + dy2);
+ glTexCoord2f(0.5, 1);
+ glVertex2f(v0[0] + dx3, v0[1] + dy3);
+
+ glTexCoord2f(0.5, 0);
+ glVertex2f(v1[0] + dx2, v1[1] + dy2);
+ glTexCoord2f(0.5, 1);
+ glVertex2f(v1[0] + dx3, v1[1] + dy3);
+
+ glTexCoord2f(1, 0);
+ glVertex2f(v1[0] + dx6, v1[1] + dy6);
+ glTexCoord2f(1, 1);
+ glVertex2f(v1[0] + dx7, v1[1] + dy7);
+ glEnd();
+}
+
+
+static float Cos(float a)
+{
+ return cos(a * M_PI / 180.);
+}
+
+static float Sin(float a)
+{
+ return sin(a * M_PI / 180.);
+}
+
+static void
+Redisplay(void)
+{
+ int i;
+
+ glClear(GL_COLOR_BUFFER_BIT);
+
+ glColor3f(1, 1, 1);
+
+ glEnable(GL_BLEND);
+ glEnable(GL_TEXTURE_2D);
+
+ for (i = 0; i < 360; i+=5) {
+ float v0[2], v1[2];
+ v0[0] = 150 + 40 * Cos(i);
+ v0[1] = 150 + 40 * Sin(i);
+ v1[0] = 150 + 130 * Cos(i);
+ v1[1] = 150 + 130 * Sin(i);
+ QuadLine(v0, v1, Width);
+ }
+
+ {
+ float v0[2], v1[2], x;
+ for (x = 0; x < 1.0; x += 0.2) {
+ v0[0] = 150 + x;
+ v0[1] = 150 + x * 40 - 20;
+ v1[0] = 150 + x + 5.0;
+ v1[1] = 150 + x * 40 - 20;
+ QuadLine(v0, v1, Width);
+ }
+ }
+
+ glDisable(GL_BLEND);
+ glDisable(GL_TEXTURE_2D);
+
+ glutSwapBuffers();
+}
+
+
+static void
+Reshape(int width, int height)
+{
+ glViewport(0, 0, width, height);
+ glMatrixMode(GL_PROJECTION);
+ glLoadIdentity();
+ glOrtho(0, width, 0, height, -1, 1);
+ glMatrixMode(GL_MODELVIEW);
+ glLoadIdentity();
+}
+
+
+static void
+CleanUp(void)
+{
+ glutDestroyWindow(win);
+}
+
+
+static void
+Key(unsigned char key, int x, int y)
+{
+ (void) x;
+ (void) y;
+
+ switch(key) {
+ case 'w':
+ Width -= 0.5;
+ break;
+ case 'W':
+ Width += 0.5;
+ break;
+ case 27:
+ CleanUp();
+ exit(0);
+ break;
+ }
+#if 0
+ if (Width < 3)
+ Width = 3;
+#endif
+ printf("Width = %g\n", Width);
+ glutPostRedisplay();
+}
+
+
+static float
+ramp4(GLint i, GLint size)
+{
+ float d;
+ if (i < 4 ) {
+ d = i / 4.0;
+ }
+ else if (i >= size - 5) {
+ d = 1.0 - (i - (size - 5)) / 4.0;
+ }
+ else {
+ d = 1.0;
+ }
+ return d;
+}
+
+static float
+ramp2(GLint i, GLint size)
+{
+ float d;
+ if (i < 2 ) {
+ d = i / 2.0;
+ }
+ else if (i >= size - 3) {
+ d = 1.0 - (i - (size - 3)) / 2.0;
+ }
+ else {
+ d = 1.0;
+ }
+ return d;
+}
+
+static float
+ramp1(GLint i, GLint size)
+{
+ float d;
+ if (i == 0 || i == size-1) {
+ d = 0.0;
+ }
+ else {
+ d = 1.0;
+ }
+ return d;
+}
+
+
+/**
+ * Make an alpha texture for antialiasing lines.
+ * Just a linear fall-off ramp for now.
+ * Should have a number of different textures for different line widths.
+ * Could try a bell-like-curve....
+ */
+static void
+MakeTexture(void)
+{
+#define SZ 8
+ GLfloat tex[SZ][SZ]; /* alpha tex */
+ int i, j;
+ for (i = 0; i < SZ; i++) {
+ for (j = 0; j < SZ; j++) {
+#if 0
+ float k = (SZ-1) / 2.0;
+ float dx = fabs(i - k) / k;
+ float dy = fabs(j - k) / k;
+ float d;
+
+ dx = 1.0 - dx;
+ dy = 1.0 - dy;
+ d = dx * dy;
+
+#else
+ float d = ramp1(i, SZ) * ramp1(j, SZ);
+ printf("%d, %d: %g\n", i, j, d);
+#endif
+ tex[i][j] = d;
+ }
+ }
+
+ glTexImage2D(GL_TEXTURE_2D, 0, GL_ALPHA, SZ, SZ, 0, GL_ALPHA, GL_FLOAT, tex);
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+ glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
+#undef SZ
+}
+
+
+static void
+MakeMipmap(void)
+{
+#define SZ 64
+ GLfloat tex[SZ][SZ]; /* alpha tex */
+ int level;
+
+ glPixelStorei(GL_UNPACK_ROW_LENGTH, SZ);
+ for (level = 0; level < 7; level++) {
+ int sz = 1 << (6 - level);
+ int i, j;
+ for (i = 0; i < sz; i++) {
+ for (j = 0; j < sz; j++) {
+ if (level == 6)
+ tex[i][j] = 1.0;
+ else if (level == 5)
+ tex[i][j] = 0.5;
+ else
+ tex[i][j] = ramp1(i, sz) * ramp1(j, sz);
+ }
+ }
+
+ glTexImage2D(GL_TEXTURE_2D, level, GL_ALPHA,
+ sz, sz, 0, GL_ALPHA, GL_FLOAT, tex);
+ }
+
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+ //glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAX_LOD, 4);
+ ////glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAX_LEVEL, 5);
+
+ glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
+#undef SZ
+}
+
+
+static void
+Init(void)
+{
+ const char *version;
+
+ (void) MakeTexture;
+ (void) ramp4;
+ (void) ramp2;
+
+ version = (const char *) glGetString(GL_VERSION);
+ if (version[0] != '2' || version[1] != '.') {
+ printf("This program requires OpenGL 2.x, found %s\n", version);
+ exit(1);
+ }
+
+ GetExtensionFuncs();
+
+ glClearColor(0.3f, 0.3f, 0.3f, 0.0f);
+
+ printf("GL_RENDERER = %s\n",(const char *) glGetString(GL_RENDERER));
+
+ glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+#if 0
+ glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
+#elif 0
+ MakeTexture();
+#else
+ MakeMipmap();
+#endif
+}
+
+
+static void
+ParseOptions(int argc, char *argv[])
+{
+}
+
+
+int
+main(int argc, char *argv[])
+{
+ glutInit(&argc, argv);
+ glutInitWindowPosition( 0, 0);
+ glutInitWindowSize(WinWidth, WinHeight);
+ glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE);
+ win = glutCreateWindow(argv[0]);
+ glutReshapeFunc(Reshape);
+ glutKeyboardFunc(Key);
+ glutDisplayFunc(Redisplay);
+ ParseOptions(argc, argv);
+ Init();
+ glutMainLoop();
+ return 0;
+}