add mupdf demo

Makefile

@@ -7,7 +7,7 @@ OBJS  = $(SRCS:.c=.o)
 CC := gcc
 CFLAGS    := -O2 -Wall $(INCLUDES) $(shell pkg-config --cflags glfw3)
 CXXFLAGS	:= $(CFLAGS) -std=c++17
-LDFLAGS   := $(shell pkg-config glfw3 --libs) -lgdi32
+LDFLAGS   := -lmupdf -lmupdf-third $(shell pkg-config glfw3 --libs) -lz -lgdi32
 
 all: $(TARGET)
 

main.c

@@ -1,6 +1,7 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <mupdf/fitz.h>
 #define IMGL3W_IMPL
 #include "opengl3_loader.h"
 #define GLFW_INCLUDE_NONE
@@ -23,6 +24,48 @@ extern "C" void userAppExit()
 }
 #endif
 
+const char *vertexShaderSource = "#version 330 core\n"
+    "layout (location = 0) in vec3 aPos;\n"
+    "void main()\n"
+    "{\n"
+    "   gl_Position = vec4(aPos.x, aPos.y, aPos.z, 1.0);\n"
+    "}\0";
+
+static const GLfloat vertices[] = {
+	0.f, 0.f,
+	1.f, 0.f,
+	1.f, 1.f,
+	0.f, 1.f,
+};
+
+struct texture
+{
+  GLuint id;
+  int x, y, w, h;
+};
+
+void ui_texture_from_pixmap(struct texture *tex, fz_pixmap *pix)
+{
+  if (!tex->id)
+    glGenTextures(1, &tex->id);
+  glBindTexture(GL_TEXTURE_2D, tex->id);
+  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+
+  tex->x = pix->x;
+  tex->y = pix->y;
+  tex->w = pix->w;
+  tex->h = pix->h;
+
+  glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
+  glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, tex->w, tex->h, 0, GL_RGBA, GL_UNSIGNED_BYTE, pix->samples);
+  glBindTexture(GL_TEXTURE_2D, 0);
+}
+
+void ui_draw_image(struct texture *tex, float x, float y)
+{
+}
+
 static void die(const char *msg)
 {
   fprintf(stderr, "%s\n", msg);
@@ -32,6 +75,13 @@ static void die(const char *msg)
 // Main code
 int main(int argc, char *argv[])
 {
+  if (argc < 2)
+  {
+    fprintf(stderr, "usage: example input-file\n");
+    return 0;
+  }
+  char *input = argv[1];
+
   if (!glfwInit())
     die("init glfw failed");
 
@@ -39,8 +89,40 @@ int main(int argc, char *argv[])
   glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 2);
   glfwWindowHint(GLFW_OPENGL_FORWARD_COMPAT, GL_TRUE);
 
+  /* Create a context to hold the exception stack and various caches. */
+  fz_document *doc;
+  fz_context *ctx = fz_new_context(NULL, NULL, FZ_STORE_UNLIMITED);
+  if (!ctx)
+    die("cannot create mupdf context");
+
+  fz_try(ctx)
+      fz_register_document_handlers(ctx);
+  fz_catch(ctx)
+  {
+    fprintf(stderr, "cannot register document handlers\n");
+    fz_drop_context(ctx);
+    return EXIT_FAILURE;
+  }
+
+  fz_try(ctx)
+      doc = fz_open_document(ctx, input);
+  fz_catch(ctx)
+  {
+    fprintf(stderr, "cannot open document\n");
+    fz_drop_context(ctx);
+    return EXIT_FAILURE;
+  }
+
+  struct texture page_tex = {0};
+  int page_count = fz_count_pages(ctx, doc);
+  printf("page_count %d\n", page_count);
+
+  fz_matrix ctm = fz_scale(1.f, 1.f);
+  fz_pixmap *pix = fz_new_pixmap_from_page_number(ctx, doc, 0, ctm, fz_device_rgb(ctx), 1);
+  ui_texture_from_pixmap(&page_tex, pix);
+
   // Create window with graphics context
-  GLFWwindow *window = glfwCreateWindow(1280, 720, "GLTEXT", NULL, NULL);
+  GLFWwindow *window = glfwCreateWindow(pix->w, pix->h, "mupdf", NULL, NULL);
   if (!window)
   {
     glfwTerminate();
@@ -58,6 +140,8 @@ int main(int argc, char *argv[])
     glfwGetFramebufferSize(window, &fbw, &fbh);
     glViewport(0, 0, fbw, fbh);
 
+    ui_draw_image(&page_tex, pix->w, pix->h);
+
     glfwSwapBuffers(window);
     glfwWaitEvents();
   }
@@ -65,5 +149,10 @@ int main(int argc, char *argv[])
   glfwDestroyWindow(window);
   glfwTerminate();
 
+  /* Clean up. */
+  fz_drop_pixmap(ctx, pix);
+  fz_drop_document(ctx, doc);
+  fz_drop_context(ctx);
+
   return 0;
 }

opengl3_loader.h

@@ -151,6 +151,7 @@ typedef khronos_uint8_t GLubyte;
 #define GL_FALSE                          0
 #define GL_TRUE                           1
 #define GL_TRIANGLES                      0x0004
+#define GL_TRIANGLE_STRIP                 0x0005
 #define GL_ONE                            1
 #define GL_SRC_ALPHA                      0x0302
 #define GL_ONE_MINUS_SRC_ALPHA            0x0303
@@ -166,18 +167,21 @@ typedef khronos_uint8_t GLubyte;
 #define GL_SCISSOR_BOX                    0x0C10
 #define GL_SCISSOR_TEST                   0x0C11
 #define GL_UNPACK_ROW_LENGTH              0x0CF2
+#define GL_UNPACK_ALIGNMENT               0x0CF5
 #define GL_PACK_ALIGNMENT                 0x0D05
 #define GL_TEXTURE_2D                     0x0DE1
 #define GL_UNSIGNED_BYTE                  0x1401
 #define GL_UNSIGNED_SHORT                 0x1403
 #define GL_UNSIGNED_INT                   0x1405
 #define GL_FLOAT                          0x1406
+#define GL_RGB                            0x1907
 #define GL_RGBA                           0x1908
 #define GL_FILL                           0x1B02
 #define GL_VENDOR                         0x1F00
 #define GL_RENDERER                       0x1F01
 #define GL_VERSION                        0x1F02
 #define GL_EXTENSIONS                     0x1F03
+#define GL_NEAREST                        0x2600
 #define GL_LINEAR                         0x2601
 #define GL_TEXTURE_MAG_FILTER             0x2800
 #define GL_TEXTURE_MIN_FILTER             0x2801