- Add Inter-Quake Model (IQM) Format support, patch by gimhael with minor modifications by myself (#4965)

- Changed model_t::md4 to model_t::modelData
- Fix R_ModelBounds for MD4, MDR and IQM models (#4966)
- Support Model format fallback similar to image formats in tr_image.c, patch by Zack Middleton (#4967)

code/renderer/iqm.h

@@ -0,0 +1,107 @@
+#ifndef __IQM_H__
+#define __IQM_H__
+
+#define IQM_MAGIC "INTERQUAKEMODEL"
+#define IQM_VERSION 1
+
+typedef struct iqmheader
+{
+    char magic[16];
+    unsigned int version;
+    unsigned int filesize;
+    unsigned int flags;
+    unsigned int num_text, ofs_text;
+    unsigned int num_meshes, ofs_meshes;
+    unsigned int num_vertexarrays, num_vertexes, ofs_vertexarrays;
+    unsigned int num_triangles, ofs_triangles, ofs_adjacency;
+    unsigned int num_joints, ofs_joints;
+    unsigned int num_poses, ofs_poses;
+    unsigned int num_anims, ofs_anims;
+    unsigned int num_frames, num_framechannels, ofs_frames, ofs_bounds;
+    unsigned int num_comment, ofs_comment;
+    unsigned int num_extensions, ofs_extensions;
+} iqmHeader_t;
+
+typedef struct iqmmesh
+{
+    unsigned int name;
+    unsigned int material;
+    unsigned int first_vertex, num_vertexes;
+    unsigned int first_triangle, num_triangles;
+} iqmMesh_t;
+
+enum
+{
+    IQM_POSITION     = 0,
+    IQM_TEXCOORD     = 1,
+    IQM_NORMAL       = 2,
+    IQM_TANGENT      = 3,
+    IQM_BLENDINDEXES = 4,
+    IQM_BLENDWEIGHTS = 5,
+    IQM_COLOR        = 6,
+    IQM_CUSTOM       = 0x10
+};
+
+enum
+{
+    IQM_BYTE   = 0,
+    IQM_UBYTE  = 1,
+    IQM_SHORT  = 2,
+    IQM_USHORT = 3,
+    IQM_INT    = 4,
+    IQM_UINT   = 5,
+    IQM_HALF   = 6,
+    IQM_FLOAT  = 7,
+    IQM_DOUBLE = 8,
+};
+
+typedef struct iqmtriangle
+{
+    unsigned int vertex[3];
+} iqmTriangle_t;
+
+typedef struct iqmjoint
+{
+    unsigned int name;
+    int parent;
+    float translate[3], rotate[3], scale[3];
+} iqmJoint_t;
+
+typedef struct iqmpose
+{
+    int parent;
+    unsigned int mask;
+    float channeloffset[9];
+    float channelscale[9];
+} iqmPose_t;
+
+typedef struct iqmanim
+{
+    unsigned int name;
+    unsigned int first_frame, num_frames;
+    float framerate;
+    unsigned int flags;
+} iqmAnim_t;
+
+enum
+{
+    IQM_LOOP = 1<<0
+};
+
+typedef struct iqmvertexarray
+{
+    unsigned int type;
+    unsigned int flags;
+    unsigned int format;
+    unsigned int size;
+    unsigned int offset;
+} iqmVertexArray_t;
+
+typedef struct iqmbounds
+{
+    float bbmin[3], bbmax[3];
+    float xyradius, radius;
+} iqmBounds_t;
+
+#endif
+